1990 VRP Mugen 125 - rebuilt

Helmut Tisberger

Here you go:
http://a-z-geballte-zweitakt-power.com/Bildergalerie

Here you go! I'll post pics of the "stock" '89 alongside so you can compare the two. There's no port modifications done to the '89, just the addition of that tiny port on the exhaust and some material has been taken off at the base to have it sit a little lower, and obviously the head is completely different for the flat-top piston.

What definitely sticks out on the Mugen is the bridges between the ports are way slimmer than on the stock cylinder.








MUGEN '89:


Stock '89:


MUGEN '89:


Stock '89:


MUGEN '89:


Stock '89:


MUGEN '89:

My hand is still hindering me from doing any work, let alone think about riding! It might be another couple of months. Meanwhile i ordered a quick-turn throttle which i hope lets me continue to ride when my movement might not get back to where it was before. I already had restricted movement before so any additional restirction might be a problem...

So right now i'm still not able to work in my garage as i can't twist any wrenches, nor do i have enough force to thighten/loosen any bolts All i can do is sort and clean and put some stickers on which is what i just did to my latest purchase: 1989 upsidedown Mugen forks.

Funny also that these actually belonged to a former opponent of mine from back in the day. They have been sitting in an angle of that guys Honda dealer ever since (that's 25 years to be exact!!). I had them serviced by my suspension guru Poletti down in Italy so they are basically as good as new





They had adjustable rebound when the stockers still wasn't offering this feature. By the way - in 1989 the stock 125cc forks were still right side up so these were pretty revolutionary back then. Only the 250 had upsidedown forks but as we all know the first Showas were really terrible. Not so these Mugen forks which were a completely different story. I still remember them to be absolutely awesome. I can't wait to actually use them again.

Just yesterday i got the correct fork guards for the above 1989 Mugen forks. They differ in shape to all following models and these days are as rare as these forks as well. I searched the net, various forums and also vintage marketplaces...but in the end a call to the same Honda dealership which had the forks collecting dust also had these guards sitting in the shelve....unbelievable: brandnew, still in the box. It's so easy to get a vintage rider happy: just get him some new plastics for his old bike



And just after i put some "wrong" colour replica stickers on my forks i got some sweet replica stickers from the Netherlands (thanks to Dirk Timmer):

The Showa needs to be orange (although the red looked perfect on those red anodized parts of the Mugen fork):

Ok-here i am again. It's now almost exactly 1 year ago i shattered my wrist and got it operated. But just the other day i finally had all the metal removed again

Bye-bye....i hope i don't need you again anythime soon:


Anyway - here's a little update on my VRP. As mentioned already i hoped to do the full 2016 italian vintage championship. But the injury delayed everything. I started riding again about end of summer only. I didn't know if the restricted movement would allow me to ride again at all. I was not able to twist the throttle full tilt so i really had some doubts it would work on track. But as it showed, with the help of the elbow, full gas was still possible

Anyway - instead of sitting at home doing nothing i decided i needed another bike for these vintage races. If ever track conditions wouldn't be ideal no way would i use my precious VRP. So i went out and looked for a decent 89 stocker to rebuild (and pimp).

Here's what i found in Italy in february:



After a complete rebuild of pretty much everything it looked like this:



As you can see no Mugen here although i'd have a 89 Mugen sitting in it's box, still brandnew, waiting to be installed. But it turned out that the german tuned Tisberger engine was so fast i would not need that Mugen yet. That bike is really,really fast even by todays standards! I started slowly and initially was only able to do 3 laps at a time before i lost grip or was completely exhausted. Remember, sitting on the couch doing nothing at all is not considered the best training for us motocrossers...

Anyway - i planned to do at least the last race of the vintage championship which was held mid october on a former GP track in Montevarchi (Tuscany). We expected nice , warm weather but it turned out it rained hard days prior and so the track was a muddy mess for timed practice in the morning. Plenty of water still on the track and very slippery conditions indeed.

It might look decent but this was on saturday still, before practices and before another rainstrom covered everything with more water...all the racing was done next day though:

[url=https://flic.kr/p/M7R87z]

Timed practice sunday morning...check the fog in the background!



Since i knew the bike would get loaded with mud and a handful to ride i did only 2 laps. I then was pretty susprised to see me having the fastest time overalll by almost 8 seconds ! That's not really a sign of how fast i went but really showing that the italians had their hands full with riding in these muddy conditions. It seems as a swiss rider i was more accustomed to these conditions. Never ever in 30 years of racing did i have such a gap on my competition. I really couldn't believe it.

[url=https://flic.kr/p/MUpTiL]

So for my first race back after 10 months i had 1st gatepick. But i already knew it would be difficult since i was completely out of shape. But starts like this helped me big time...i actually go the holeshot in both races that day

VIDEO:


In the end i got 2x 2. for 2nd overall. I was stoked and really happy. My wrist would hold up and i had big fun and a relief. Everything was doing fine. Even my "practice"-bike was showing to be an absolute rocketship.

Both my VRP and my "practice"-bike got washed and are ready for more prep during the offseason:


Just lately i was able to get some nice '89 Mugen suspensions for my bike:
[url=https://flic.kr/p/P6wQwr]



That's basically the very first USD forks. In '89 it was just the CR 250 which had them, but Mugen offered full forks also for the CR 125. Not just Mugen inserts but rather full forks.

So here we are. I have now both bikes outfitted with Mugen USD forks. The picture below got taken just 1 week ago at a big event in Italy (about 20 degrees celsius):


While this one below got taken only 2 days later near Zurich(Switzerland) at just a hair over freezing temperatures:


So - as is i have another 1 month break to have the empty holes in my wrist heal...but with bikes like these sitting in my garage i really can't wait for the 2017 season to start

I wish you all merry christmas and a injury-free 2017 season!!!

Over here in Switzerland we have freezing temperaturs and quite a bit of snow thus no riding since about 6 weeks. It was just enough now to have my wrist heal again after they removed all the metal....

So i jumped on the occasion when my good friend Gherardo from Sicily/Italy invited me to come down and spend two days riding his bikes. He has two (!!) such VRP Mugen Hondas. Since last saturday was also Carlo Veronas birthday (Mr. VRP) we took some photos to send him our best wishes...





The bikes were a little undersprung for me since he weighs about 25 lbs less than me. So in certain jumps i couldn't goo all out to prevent bottoming too hard. But we still had a great time using his Mugen powered bikes on a really cool track:

-----> VIDEO:
[youtube]https://www.youtube.com/watch?v=WFU0Cc_Mryo[/youtube]





Te next day we wernt to another track where you had orange trees in the paddock. Too cool


In Italy you can't miss a nice Cappuccino at the bar for breakfast:


....and a nice Pizza with some italian beer in the evening:

Sounds cool. Do you have a link to those videos?

Me too - i'm using my 1990 Mugen equipped bikes against modern 450s over here. And i also plan to use my 89 this year as i got it really fast, even without the use of a Mugen.

Found it - Unadilla looks really nice!

What i like the most about these vintage races i do, especially in Italy, is the relaxed and friendly athmosphere. There is no bad word in the pits! All one big family, addicted motoheads with nice bikes that share their passion. It's like those 15 minutes out on track loose their importance really. It's more the sharing of our passion than a competition.

Even though when racing you do race, you do battle, you do suffer just as you did back in the day...for me all that misses is the pain and the suffering as now it's done for joy. If you get passed that other guy merits it and it's not that you want to kill him anymore

If someone has a nice new part on his bike you give him credit and don't ignore him just like you did when still racing for championships...

It's the kind of athmosphere where the guy next to you in the paddock, which you have never seen before, has his wife prepare an additional plate of pasta. I haven't asked or anything...such never happened when i raced for points at younger age. Awesome support and friendship among each other....like Family!



And an hour later you line up next to that guy when racing for Vintage championship points (Campionato italiano motocross d'epoca):

Below my start from Montevarchi/Tuscany from 2016. A former GP track. I took the holeshot in both races...no Mugen, no 144cc either

[youtube]https://www.youtube.com/watch?v=d71FjdRVPSA[/youtube]

Top 3 from practice that day just prior to the gate drop...one big friendship
[url=https://flic.kr/p/N5vacH]

Niiice polish job on your tank

Do i see modern forks on your bike? That's something you aren't allowed over here! Bikes&parts need to be of the era. No modern forks, no oversized brakes, no 19" rear wheels...

I personally don't think that this kind of seal is needed. Especially not if you would run a mesh on the front numberplate which would bring air down through these channels right into the airbox.

I definitely agree that there is no more power to be generated by these channels, but they sure make for the same effect as your trying to block "hot" air from coming in from below by instead bringing some fresh air down there. I'd say by putting that aluminium foil you also restrict airflow to some degree which might hurt more.

it's really difficult to find these and if you should find one expect to pay huuuuge dollars...

I sent you a PM.

Here's a look at some of those HPP covers
Stock
Mugen
HPR (adjustable preload for HPP)
Wirtz (adjustable preload for HPP)

Meanwhile i built yet another 89 from the ground up. I needed a spare for the spare since also my racebike got too nice to put through mud...

[url=https://flic.kr/p/UMUeRo]

[url=https://flic.kr/p/Xf4WNs]

Anyway - i now have my garage full of nice Mugen powered 125cc Hondas:
[youtube]https://www.youtube.com/watch?v=D0uuE05Ci30[/youtube]