1990 VRP Mugen 125 - rebuilt

wolfy0067
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9/14/2017 5:15pm

New fork and shock work so good, huge upgrade in front brake power
wolfy0067
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9/14/2017 5:17pm

Couldn't help but post the 250, she got a full rebuild this winter also
MaxPower
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9/14/2017 6:56pm Edited Date/Time 9/14/2017 6:59pm
How is your wrist Lucky Nino?
It's crazy the hardware Dr's can use to fix our bones
luckynino
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9/14/2017 9:57pm
Ive got the one thing none of u mugen guys have.... mugen crossbar pads....[img]https://p.vitalmx.com/photos/forums/2017/09/14/214741/s1200_IMG_1913.jpg[/img]
Ive got the one thing none of u mugen guys have....

mugen crossbar pads....

Nono-you're not alone with your barpads... Wink



Then once during e rebuild i was able to do this pic:
Lot's of VRP aluminium here Smile
1

The Shop

luckynino
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9/14/2017 10:03pm
MaxPower wrote:
How is your wrist Lucky Nino?
It's crazy the hardware Dr's can use to fix our bones
The wrist is actually ok. It's now the shoulder that bothers me and i should have it examined and done another MRI to detect if i really needs to be operated. I hurt it at the same incident where i shattered my wrist only back then the wrist pain obviously was the center of the focus and the painkillers i had to take for almost 4 weeks kept the shoulder under control. It was after i quit with painkillers that the shoulder came up and i did half a year of therapy to it...then they still did an MRI where they discovered a partly rupture of my upper bizeps muscle attachment which they would have liked to operate. I refused to do so last year but now the pain is back, especially during the nights, and i have severely restricted movement as well...that thing needs to be fixed which will mean 3 months out at least!
luckynino
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9/14/2017 10:26pm Edited Date/Time 9/14/2017 11:35pm
wolfy0067 wrote:
[img]https://p.vitalmx.com/photos/forums/2017/09/14/214744/s1200_IMG_2322.jpg[/img] New fork and shock work so good, huge upgrade in front brake power

New fork and shock work so good, huge upgrade in front brake power
That's some nice bikes you have there!

But i just think the way the italians handle the vintage racing is what it is all about: have your bike built with parts that were able BACK IN THE DAY. Just as it were a timeshift. So you can't put modern forks or shocks, modern,oversized brakes. etc...the bike has to be ridden just like back in the day.

That's why i went out and just lately bought a 3rd (!!) pair of Mugen USD forks which just now get serviced by my suspension guru Poletti in Italy. I should have them back soon and they will go on my latest '89 build.

The stock, right-side-up forks are for sure a step behind in performance. Those Mugen forks though are pretty close to modern forks and comply with the techincal requirements of italian vintage racing. In the end it's all about racing OLD bikes, isn't it? After my thumb injury i did a race against 450s using my 89. Back then still with the traditional, right-side up forks. It's only then that you realize that especially the lower legs sticking out under the axle are a pain. Especially if you are the only one dragging them in rutted turns. I eventually had to change lines to avoid getting stuck in rutted corners. This way i also avoided the biggest braking bumps coming into corners which compensated for the forks deficits even more Wink But as you mentioned above - it's also the small rotors of the brakes that are behind actual machinery. I got a little improvement by using AP pads (front ones are AP LMP294 ORR). They offer slightly more aggressive power than the awesome stock Honda pads. This way you can also race with the small 240mm stock rotors.

I had a hard time to find any data or info on those 89 Mugen forks but finally found some pics in a french guys Flickr account just to prove those forks really existed back then already:

1989 - Frederic Bolley riding a CR 125 with Mugen USD forks and also a VRP swingarm
[url=https://flic.kr/p/XuqHVk]
wolfy0067
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9/15/2017 5:38am
Neno, I respectfully disagree, back in the day when I ran pro motocross the factory bikes had some of the most advanced parts available, power valves, huge diameter cartridge forks, coke bottle swing arms, huge brakes , frames titanium fasteners and such. Privateers were left with back yard tuners doing shim shuffles to whimpy 38mm fork and 10mm shock shafts, just looking at the photo you post shows this, not everyone can afford or find VRP or Mugen parts. My opinion is if I can trick my bike out as factory's did in the past, these part are radially available to everyone and the class allows, i'm doing it. With that said we do have classes that require stock equipment or should I say stock appearing equipment, most are cheating. Let me ask, how do you think you would do racing a properly setup CR125 against your trick Alluminum framed, Mugen engine , Mugen suspension, alloy tank equipped machine. I'm thinking your ability would still see you winning.
Regards, Dave
luckynino
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9/15/2017 9:23am Edited Date/Time 9/15/2017 9:30am
wolfy0067 wrote:
Neno, I respectfully disagree, back in the day when I ran pro motocross the factory bikes had some of the most advanced parts available, power valves...
Neno, I respectfully disagree, back in the day when I ran pro motocross the factory bikes had some of the most advanced parts available, power valves, huge diameter cartridge forks, coke bottle swing arms, huge brakes , frames titanium fasteners and such. Privateers were left with back yard tuners doing shim shuffles to whimpy 38mm fork and 10mm shock shafts, just looking at the photo you post shows this, not everyone can afford or find VRP or Mugen parts. My opinion is if I can trick my bike out as factory's did in the past, these part are radially available to everyone and the class allows, i'm doing it. With that said we do have classes that require stock equipment or should I say stock appearing equipment, most are cheating. Let me ask, how do you think you would do racing a properly setup CR125 against your trick Alluminum framed, Mugen engine , Mugen suspension, alloy tank equipped machine. I'm thinking your ability would still see you winning.
Regards, Dave
Sure they had trick parts back in the day. And it's those parts i am talking about that you are able to use! Just not modern forks or whole CRF front-ends etc....it has to be parts of the era just like my VRP which is about as trick as a bike can be.

I'm actually going almost as fast with my 89 bikes as opposed to my "modern" AF build. The difference is really minor and what hurt the most was the right-side up forks and the front brake and the curved seat up on the tank which makes for a old-fashioned riding compartment. Other than that - my tuned 89 engine is blazing fast (definitely much faster than a '17 YZ 125), the suspensions now do a good enough job to go fast as well. Interesting though that the old settings my suspension man still has don't work anymore on todays tracks. We now have different jumps, higher speeds, different bumps from the thumpers....seems weird but old setting data just doesn't work anymore. All much too soft. But anyway - these older bikes just tire you out a little more as you do have to hold the handlebar a little thighter as on the modern bikes. But it's really fun how fast you accustom to the older bikes. At first you think no way...but once i actually spent some time on them i got comfy and enjoyed them big time.
wolfy0067
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9/15/2017 3:23pm
Well, I guess we can agree taking an old bike to a modern event and kicking their buts just feels better than on modern equipment, experienced the same deal with the lower fork legs, you can really feel the legs draging in the turns
luckynino
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9/15/2017 9:23pm Edited Date/Time 9/15/2017 9:25pm
What's definitely cool is also the stares you get in the pits when you show up with old bikes: there's always people come to have a look, you are always chatting with someone asking questions about it...they don't care about the latest '17 bike sitting next to them but they come over to see the old smokers instead. Especially when they see they can get ridden for real Wink That's really cool.

luckynino
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10/11/2017 9:58am
As mentioned before i just mounted some '89 Mugen USD forks onto my 3rd CR 125. So now all three have the same forks. I now have three super tricked out bikes for vintage racing BUT my bad shoulder won't let me ride my bikes anytime soon.I'll get it operated soon and will have a 3 month rehab...oh well Wink

Age correct suspension, and really not far behind to modern suspension.




quiknic
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11/4/2017 10:35pm
luckynino wrote:
As mentioned before i just mounted some '89 Mugen USD forks onto my 3rd CR 125. So now all three have the same forks. I now...
As mentioned before i just mounted some '89 Mugen USD forks onto my 3rd CR 125. So now all three have the same forks. I now have three super tricked out bikes for vintage racing BUT my bad shoulder won't let me ride my bikes anytime soon.I'll get it operated soon and will have a 3 month rehab...oh well Wink

Age correct suspension, and really not far behind to modern suspension.




Sweet bikes and well done!

I do have a question on the VRP swing arm as I just purchased one for my latest 89 CR250 build. Do these run the standard bearings and chain guide. Just ordered the bearings but it looked like the stock chain guide will not fit?

Do you have any spare VRP or HRC parts that you are looking to sell?

Thanks!
luckynino
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11/4/2017 11:29pm Edited Date/Time 11/5/2017 7:20am
Uhhh-i hope you got a "real" VRP swingarm as there's too many fakes sold out there!

Most probably though you got one that might fail when used....there's some guys in Italy selling fakes for good money. Just check the picture below what can happen to them...

VRP didn't make too many of those swingarms. And the ones made got used back in the day so if you find such swingarms "new" you can almost be assured they're actually replicas. Most of the time they also use the fused center part of the stock swingarms when real VRP swingarms don't use no parts of the stocker.

Yes - VRP used stock parts as far as bearings and chainguides are concerned.



No - i don't have any such parts for sale.
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quiknic
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11/5/2017 12:01am
Thanks for the feedback, do you have any pictures of the VRP swing arm unmounted or closeups and will there be any specific markings that I should look for?
Bearuno
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11/5/2017 5:34am
Nino - do you feel free to give a name to the suspect (well, Crap) Swing arms ?

You might save a few people a large amount of grief. I know of one manufacturer that seems to use the std castings In Italy, but their site, and enormous amount of diverse bike frames and parts would indicate they'd be responsible enough to use decent materials and the appropriate heat treatment for the materials used.

That's a hell of a 'banana' you've pictured, and I daresay it still cost the owner a pretty penny.
luckynino
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11/5/2017 7:52am Edited Date/Time 11/5/2017 7:59am
No - i won't give names here. You'd think it is a reputable source though.It's a shame as there's quite a few people that might pay serious money for parts like this.

This is a close-up of my VRP swingarm (attached to a full VRP chassis...parts me and my dad bought directly from Mr. Carlo Verona back in the dayWink )


Check the middle section on the VRP. Unlike the stocker it has no fused center-section:



IF you should need a cokebottle swingarm i'd get in touch with Boris from Bormi Parts in Italy! Bormi Parts can be found on Facebook and he is a true master in aluminium welding!! He races vintage MX himself so he has the same virus we have...Below one of his 89 CR Swingarms...a true work of art just like the real VRPs. He does also nice aluminium gas tanks and airboxes, subframes etc...if you need a custom aluminium part Boris is your man!

He stamps his parts with his own name. No fake VRP stamps here unlike many other parts you can get on the market!



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Bearuno
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11/5/2017 5:59pm Edited Date/Time 11/5/2017 6:12pm
Bormi Parts are the ones I was referring to as being a company, with it's wide variation of products / projects, that I thought would be trustworthy.

But Nino, that picture of the Banana Bend Swingarm , if you know of the absolute provenance of (the manufacturer) , should have the name of the manufacturer revealed. By producing something like that, and especially if they consistently produce pretty garbage like that, they've lost the right to anonymity.

You'd be doing the right thing in placing a name to the product. But hey, perhaps they are 'connected' , and they could make things very unpleasant for you - as with all of your toys, I'm sure you are well known at the circuits, and I daresay you get to Italy from Switzerland (where you're from?) quite often ..... Woohoo

I'll be doing my own Coke Bottle Swingarm . I've made frames for decades. I make my own 'things'.

I've got a few spare swingarms, one of which I will use the front casting from ( as Bormi do with a few of their's) for when / if I ever do my CR500 back up as a Garage Queen. No, I won't do that, I'll look out for another 500 to do that to. I have a PDS / TTX'd rear end on my CRE500 that I did, that I love.
gdel324
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3/21/2018 4:17am
luckynino wrote:
I want to share my fully rebuilt Vintage racebike with you guys: [b][u]1990 VRP Mugen 125[/u][/b] It was my racebike back in '90/'91 and even into...
I want to share my fully rebuilt Vintage racebike with you guys:

1990 VRP Mugen 125

It was my racebike back in '90/'91 and even into '92 for the Swiss Inter 125cc championships and i was eligible to do worldchampionships (GPs) as well. After the '92 season it got teared down and i stored the whole chassis in my dads basement. It stayed there for over 20 years....

It's in 2012 that i finally started rebuilding my bike. That was the year i almost gave up riding my 125cc bikes i kept to date.... I bought myself a KTM 350 fourstroke but actually never liked the way they need to be ridden. I missed the attack style riding, the screaming engine, the flickable feel,...even though i'm 47 years old now i still like to go full-throttle and attack berms etc. That was all missing with the fourstoke and i really lost the fun while riding. And let's be honest- at my age this is what it's all about: having fun on the bike !! That's when i decided to do a 125 AF (with actual CRF chassis) but also got interested in rebuilding my old racebike. I sold the 350 and from then on concentrated on my 125 Hondas. So actually i have 3 of them in my garage...

The custom, aluminium VRP chassis is something very,very exotic.

VRP is an italian brand: Verona Racing Parts.
Back then in the US VRP got distributed by On the Line Racing

Carlo Verona was the main man behind all this and he was/is really a genius. Back then the GPs went over 40 minutes + 2 laps so almost every GP rider needed large capacity fuel tanks. VRP was famous for doing those as well as rear aluminium subframes. They also did those nice swingarms for HRC but also for Kawasaki works bikes. And finally in '89/'90 they did this unique aluminium chassis for Honda CRs. Remember - that's 8 years before Honda offered the 1st aluminium frame on the '97 CR 250 ! Later on Carlo Verona also did a full 500cc GP roadracer (chassis AND engine...all by VRP!). These days he does engines for speedboats and has several worldchampionships to his credit.

The aluminium frame wasn't any lighter than the stock steel frame but much stiffer. It really changed the way the bike handled and how the suspension components would perform. It was leaps better.

Anyway - enjoy the pictures:
http://www.vitalmx.com/community/luckynino,45103/setup,45296






Mugen kitted engine




This is in 2012 when the rebuild started:


According to Carlo Verona only 12 such frames got ever produced. Mine was supposed to be used by Georges Jobé when he attempted to win the 125cc title but VRP finished the whole chassis too late so Jobé decided to compete with stock chassis instead (and we all know he didn't succeed to win the title).









Original VRP catalogue:






Original picture of 1991


My Mugen collection Wink


The Mugen-equipped engine:


I run the exact same engine in my current CR 125 AF (with CRF chassis)....the engine now enters it's 25th season !!!! And it's still running strong. I can still beat todays actual machinery ('15 KTM etc.) Tongue


Hi I'm new to group but last year procured the first model MX bike I ever owned /raced. I was going to do a full stock or as much as I could restoration,but the Mugen concept is making my brain explode. I gotta try atleast a cylinder modification and see difference of the 95 cylinder with a 144 kit on it. I'm happy with power but it is all mid/top.do he Mugen bring anymore bottom end or is it same as I got..also are there any other mods I can do to get desired effect.i have two spare 125 cylinders/head/PV.. I can use that could be modified.

just curious if is even possible to get a call her as well..

Ty gary
gdel324
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3/21/2018 4:19am
Ive got the one thing none of u mugen guys have.... mugen crossbar pads....[img]https://p.vitalmx.com/photos/forums/2017/09/14/214741/s1200_IMG_1913.jpg[/img]
Ive got the one thing none of u mugen guys have....

mugen crossbar pads....

Ohh the bike is a 90 cr125
gdel324
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3/21/2018 4:21am
Ohh the bike is a 90 cr125
luckynino
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3/21/2018 2:17pm
gdel324 wrote:
Hi I'm new to group but last year procured the first model MX bike I ever owned /raced. I was going to do a full stock...
Hi I'm new to group but last year procured the first model MX bike I ever owned /raced. I was going to do a full stock or as much as I could restoration,but the Mugen concept is making my brain explode. I gotta try atleast a cylinder modification and see difference of the 95 cylinder with a 144 kit on it. I'm happy with power but it is all mid/top.do he Mugen bring anymore bottom end or is it same as I got..also are there any other mods I can do to get desired effect.i have two spare 125 cylinders/head/PV.. I can use that could be modified.

just curious if is even possible to get a call her as well..

Ty gary
Mugen kits enhanced power big time but it's all mid-top. If you are looking for bottom-end a 125 is not the way to go anywayWink

BUT the 144 mod on the HPP is also not your best way to get more bottom as with the bigger bore you need to trim/shave the HPP valves which results in a very poor working exhaust system. By cutting the HPP valve shorter you loose it's effectiveness. Siuch a 144 has a little more bottom because of the bore BUT since the exhaust system is just half as effective the gains aren't that much. And on top of it a 144 won't rev as good as the 125...for me not the ideal setup.

For more bottom on the HPP try the following:

First of all you need to make sure your HPP exhaust system is working properly. I did a long thread on how to set up the HPP here:
https://thumpertalk.com/forums/topic/1207620-honda-125-hpp-setup-tips-t…

Although most will tell you a bigger carb will make for a weak bottom end or even a loss of bottom-end...it's not the case when you combine it with a modified governor! The bigger carb enhances mid-top power quite a bit but makes for a void just before you enter the powerband. So you definitely need a finger on the clutch to get the revs up into the meat of the powerband. I found out that the bigger carb needs a different timing on the exhaust valve. The valves need to be closed a little longer. You can achieve it by altering the preload on the governor spring by adding shims.

What you will definitely need are the HPP valves&guides off the 98/99 model!! These HPP valves are the best for all HPP engines. Regardless of their age (90-99). These valves have a L-shape and the guides have a groove where that L-shape fits into.This makes for a much better seal when closed and therefore enhances bottom end.

Check the picture below where i placed a 90-97 valve (upper pair) next to a 98/99 HPP valve (the one in the front). Check the L-shape and the according groove in the guide!


This is the 90-97 valves which show massive blow-by when closed. They are supposed to actually lower the exhaust port but as you can see the gases flow by anyway.


Here's the 98/99 valves and just where the red arrow points to there is absolutely no blow-by as the L-shape makes for a perfect seal:


To help bottom power you might raise compression some. Easiest way is to use a thinner base gasket for the cylinder. Stock gaskets are 0,5mm....try a 0,4mm which will lower the cylinder and therefore raise compression. Same effect as having the head machined down 0,1mm but much cheaper and reversible Wink

Placing some exhaust spacers also helps in the low-end. Using such spacers between exhaust collector and exhaust pipe effectively makes for a longer front section which helps low-end. Easily done and pretty effective as well. Try adding 3 or 6mm


And obviously you need a good exhaust for low-end. I found that italian Messico or HGS give plenty of mid without sacrificing too much top power. Just stay clear of Pro Circuit and DEP which really don't offer any low-end or mids to talk about.

1
quiknic
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3/21/2018 8:06pm
luckynino wrote:
Uhhh-i hope you got a "real" VRP swingarm as there's too many fakes sold out there! Most probably though you got one that might fail when...
Uhhh-i hope you got a "real" VRP swingarm as there's too many fakes sold out there!

Most probably though you got one that might fail when used....there's some guys in Italy selling fakes for good money. Just check the picture below what can happen to them...

VRP didn't make too many of those swingarms. And the ones made got used back in the day so if you find such swingarms "new" you can almost be assured they're actually replicas. Most of the time they also use the fused center part of the stock swingarms when real VRP swingarms don't use no parts of the stocker.

Yes - VRP used stock parts as far as bearings and chainguides are concerned.



No - i don't have any such parts for sale.
I have contacted the seller since receiving my swing arms as it sure looks to be the same as what is pictured above but he is swearing that the swingarm that I purchased is VRP and even offered a 5 year warranty on any issues with it.

I had placed a large order all at one time since it was being shipped from Italy to the U.S. and also bought what was supposed to be a Factory Suzuki swingarm but it too looks to be from the same cloth or can if you will... Take a look and let me know your thoughts as all of the other parts, seat covers and plastics were the real deal.











luckynino
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3/21/2018 10:34pm
quiknic wrote:
I have contacted the seller since receiving my swing arms as it sure looks to be the same as what is pictured above but he is...
I have contacted the seller since receiving my swing arms as it sure looks to be the same as what is pictured above but he is swearing that the swingarm that I purchased is VRP and even offered a 5 year warranty on any issues with it.

I had placed a large order all at one time since it was being shipped from Italy to the U.S. and also bought what was supposed to be a Factory Suzuki swingarm but it too looks to be from the same cloth or can if you will... Take a look and let me know your thoughts as all of the other parts, seat covers and plastics were the real deal.











Well - at least to me it's pretty obvious the swingarm is not original but new made.

I know from Mr. Verona (VRP) himself that he never used the stock, cast middle section to make his swingarms. Yet that guy sells all of his swingarms with the cast middle section. IF it were original swingarms they would be like 30 years old and would have stayed on a shelf this long too.....and they would show age in some sort. Either colour (slight oxidation) or light scratches...yet these are all brandnew.

This alone to me is proof that certain guys are doing big business by making replica parts and by selling them as originals at steep prices.

Check the middle section of the VRP swingarm! It's not a cast part cut out of a stock swingarm but rather made out of aluminium sheet. All handmade! And that guy sells swingarms readily available for all bikes of the era...when in reality VRP made only a handful of these swingarms at the time. Not it seems they were mass produced and were a item that was used on a lot of bikes - NOT SO ! VRP is a very small company with just 2 guys welding parts. No mass production.




VRP catalogue...again check the middle section of the swingarm:



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Smed
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3/22/2018 12:52am Edited Date/Time 3/22/2018 12:53am
luckynino wrote:
Uhhh-i hope you got a "real" VRP swingarm as there's too many fakes sold out there! Most probably though you got one that might fail when...
Uhhh-i hope you got a "real" VRP swingarm as there's too many fakes sold out there!

Most probably though you got one that might fail when used....there's some guys in Italy selling fakes for good money. Just check the picture below what can happen to them...

VRP didn't make too many of those swingarms. And the ones made got used back in the day so if you find such swingarms "new" you can almost be assured they're actually replicas. Most of the time they also use the fused center part of the stock swingarms when real VRP swingarms don't use no parts of the stocker.

Yes - VRP used stock parts as far as bearings and chainguides are concerned.



No - i don't have any such parts for sale.
quiknic wrote:
I have contacted the seller since receiving my swing arms as it sure looks to be the same as what is pictured above but he is...
I have contacted the seller since receiving my swing arms as it sure looks to be the same as what is pictured above but he is swearing that the swingarm that I purchased is VRP and even offered a 5 year warranty on any issues with it.

I had placed a large order all at one time since it was being shipped from Italy to the U.S. and also bought what was supposed to be a Factory Suzuki swingarm but it too looks to be from the same cloth or can if you will... Take a look and let me know your thoughts as all of the other parts, seat covers and plastics were the real deal.















Nino, Do you know who made these swingarms sold by PC? Are they VRP? They also sold subframes, VRP? This ad is from a mid 80's MXA mag.



















luckynino
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3/22/2018 5:53am
I don't know for sure but i'd say yes - those were VRP parts.

VRP also did HRC swingarms back in the day and still did aluminium parts for HRC in recent years.

gdel324
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3/22/2018 8:59am
gdel324 wrote:
Hi I'm new to group but last year procured the first model MX bike I ever owned /raced. I was going to do a full stock...
Hi I'm new to group but last year procured the first model MX bike I ever owned /raced. I was going to do a full stock or as much as I could restoration,but the Mugen concept is making my brain explode. I gotta try atleast a cylinder modification and see difference of the 95 cylinder with a 144 kit on it. I'm happy with power but it is all mid/top.do he Mugen bring anymore bottom end or is it same as I got..also are there any other mods I can do to get desired effect.i have two spare 125 cylinders/head/PV.. I can use that could be modified.

just curious if is even possible to get a call her as well..

Ty gary
luckynino wrote:
Mugen kits enhanced power big time but it's all mid-top. If you are looking for bottom-end a 125 is not the way to go anyway;) BUT...
Mugen kits enhanced power big time but it's all mid-top. If you are looking for bottom-end a 125 is not the way to go anywayWink

BUT the 144 mod on the HPP is also not your best way to get more bottom as with the bigger bore you need to trim/shave the HPP valves which results in a very poor working exhaust system. By cutting the HPP valve shorter you loose it's effectiveness. Siuch a 144 has a little more bottom because of the bore BUT since the exhaust system is just half as effective the gains aren't that much. And on top of it a 144 won't rev as good as the 125...for me not the ideal setup.

For more bottom on the HPP try the following:

First of all you need to make sure your HPP exhaust system is working properly. I did a long thread on how to set up the HPP here:
https://thumpertalk.com/forums/topic/1207620-honda-125-hpp-setup-tips-t…

Although most will tell you a bigger carb will make for a weak bottom end or even a loss of bottom-end...it's not the case when you combine it with a modified governor! The bigger carb enhances mid-top power quite a bit but makes for a void just before you enter the powerband. So you definitely need a finger on the clutch to get the revs up into the meat of the powerband. I found out that the bigger carb needs a different timing on the exhaust valve. The valves need to be closed a little longer. You can achieve it by altering the preload on the governor spring by adding shims.

What you will definitely need are the HPP valves&guides off the 98/99 model!! These HPP valves are the best for all HPP engines. Regardless of their age (90-99). These valves have a L-shape and the guides have a groove where that L-shape fits into.This makes for a much better seal when closed and therefore enhances bottom end.

Check the picture below where i placed a 90-97 valve (upper pair) next to a 98/99 HPP valve (the one in the front). Check the L-shape and the according groove in the guide!


This is the 90-97 valves which show massive blow-by when closed. They are supposed to actually lower the exhaust port but as you can see the gases flow by anyway.


Here's the 98/99 valves and just where the red arrow points to there is absolutely no blow-by as the L-shape makes for a perfect seal:


To help bottom power you might raise compression some. Easiest way is to use a thinner base gasket for the cylinder. Stock gaskets are 0,5mm....try a 0,4mm which will lower the cylinder and therefore raise compression. Same effect as having the head machined down 0,1mm but much cheaper and reversible Wink

Placing some exhaust spacers also helps in the low-end. Using such spacers between exhaust collector and exhaust pipe effectively makes for a longer front section which helps low-end. Easily done and pretty effective as well. Try adding 3 or 6mm


And obviously you need a good exhaust for low-end. I found that italian Messico or HGS give plenty of mid without sacrificing too much top power. Just stay clear of Pro Circuit and DEP which really don't offer any low-end or mids to talk about.

Nino,

Thank you for all your help and knowledge I will definitely be working together with my mechanic to acheive this. YOU THE MAN
Bearuno
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3/22/2018 11:07pm
quiknik, heed what Luckynino has written. The CR swingarm absolutely is Not a VRP. It's got the original cast front section, and I recognise standard chain guide mounts and the caliper carrier mount. They've just been cut off the original swingarm, and welded onto the pressed halve arms they've made. It's easy to do - in the process of making my PDS rear end for my 500 I removed them to transfer them to opposite sides, as I ran the swingarm upside down for my adjustable PDS mount to be placed in the Rocker recess.

I don't know enough about Suzuki one pictured to offer an informed opinion.

I really hope you've got a Bormi Parts swingarm, or at least a Properly made one, and Not one of the 'unnameable' ones that Luckynino put a picture up of.

If you look up Bormi Parts, and search through their pictures, you'll see they've done a variety of 'Coke Bottle' CR swingarms. Ones with fabricated front sections, ones with the full std cast front sections, ones with the cast std section, but with machined swingarm bearing housings, ones with cast front sections, but with a weld across them to emulate some works swingarms.

But, your 'seller' is Bull Shitting you on the CR one being a VRP. I Hate Bull Shitting / dishonest sellers - I've been ripped off a few times, and it's made me very, very cynical and untrusting.
Rocky739
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Indianapolis, IN, USA
3/23/2018 5:58am
Thanks for the information on the HPP setup! Helped emensily when assembling my 97 cylinder.
I’ve got a eBay search going for the 98-99 powervalves. I was scratching my head about the gap when I took it apart?!? Courious about why Honda would have made them so leaky, kinda defeats the entire point.
quiknic
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Fantasy
3/24/2018 9:50pm
Bearuno wrote:
[b]quiknik[/b], heed what Luckynino has written. The CR swingarm absolutely is Not a VRP. It's got the original cast front section, and I recognise standard chain...
quiknik, heed what Luckynino has written. The CR swingarm absolutely is Not a VRP. It's got the original cast front section, and I recognise standard chain guide mounts and the caliper carrier mount. They've just been cut off the original swingarm, and welded onto the pressed halve arms they've made. It's easy to do - in the process of making my PDS rear end for my 500 I removed them to transfer them to opposite sides, as I ran the swingarm upside down for my adjustable PDS mount to be placed in the Rocker recess.

I don't know enough about Suzuki one pictured to offer an informed opinion.

I really hope you've got a Bormi Parts swingarm, or at least a Properly made one, and Not one of the 'unnameable' ones that Luckynino put a picture up of.

If you look up Bormi Parts, and search through their pictures, you'll see they've done a variety of 'Coke Bottle' CR swingarms. Ones with fabricated front sections, ones with the full std cast front sections, ones with the cast std section, but with machined swingarm bearing housings, ones with cast front sections, but with a weld across them to emulate some works swingarms.

But, your 'seller' is Bull Shitting you on the CR one being a VRP. I Hate Bull Shitting / dishonest sellers - I've been ripped off a few times, and it's made me very, very cynical and untrusting.
Bearuno - I knew it was trouble as soon as I received them and opened the boxes as they did not match the pictures on their website 100% but i was hoping that I was wrong... I spent $2700 on a large order of parts with these F#!K3RS and as they are located in Italy and I am in the USA it makes it pretty difficult to run on over and break some limbs to get my money back. I gave them an opportunity to return my money and I would have shipped back the swingarms but again they refuse and swear through their teeth that I had received VRP parts. They did however say that they would offer a 5 year warranty which judging by their previous lies I would not hold much faith in.

These swing arms were definitely made by the same person, like Luckynino said there is no oxidation or signs of wear and age on them, they also delayed getting them shipped for sometime and were probably making them after I sent the bank transfer since they would not do PayPal. So much for buying a VRP swingarm for my CR250 and a Factory Suzuki swingarm for my RM125 as like you I am very cynical and untrusting of folks now. Good money gone up in flames, but hey at least the small parts that I bought turned out to be real.

Steer clear of MASTERCROSS in ITALY unless you too like burning your hard earned cash!
Bearuno
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5463
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Location
AU
3/24/2018 11:19pm
Lets hope that yours, from MASTERCROSS, are Not from the same people as the one pictured by Luckynino.

It may be a good product, using good materials, and with the correct post welding heat treatment / ageing procedures. Generally, the materials used will be in a '0' / annealed condition ( though, terms for materials specs do differ around the World) so as to be form-able into the two halves, to then be welded and treated as the material used requires for strength.

I Do hope you've got a good pair of Swingarms for your money! If you have a local Engineering firm that specializes in Aluminium fabrication, or a College / Uni with an Engineering faculty, they could check for materials / heat treatment / hardness specs of the Arms.

That your suppliers appear to be blatantly lying about the provenance of the Swingarms - well, it indicates a significant 'bent' (sorry, couldn't resist the pun relating to the Banana Swingarm) towards flim flamery on their part.

As the name - MASTERCROSS - is now out there, perhaps Luckynino can confirm that Banana'd Swingarms provenance, if it is Indeed a MASTERCROSS product?

It does no one any service here to not name a badly made product.

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