Suzuki RM250 Enduro Build - Complete with Pics

To start I tore the bike down to the frame to get it powder coated gloss black.
I was super lucky and managed to bag a mint condition light speed carbon sump guard and carbon frame guard set over winter. Super light and look awesome.
Finished off with Ti bolts.




With the engine out I rebuilt the top end using the OEM top end rebuild kit supplied. This was the first time this engine had been apart, there wasn’t a spanner mark to be seen on any of the bolts/nuts.

I took a squish measurement which came out at 1.38mm. Not bad, but I knew there were gains to be had. I rebuilt the top end using a 0.4mm Athena base gasket, which took the squish to 1.28mm. I’ve done this mod before on my last RM and it was good for a small overall boost in power and throttle response. I also fitted a V-force reed cage, Hinson Clutch Cover and to finish off I replaced majority of the steel OEM bolts with titanium bolts.



I had a Rekluse EXP disc left over from my RMZ450 build. I used it in the 450 for around 15 hours before deciding against it and removing it. Lucky for me the Rekluse EXP also works in the RM250. I changed out the tension springs to suit the engines speeds of the RM and fitted it. I then added a NEXT Components unbreakable clutch lever.
From previous Enduros I was burning up my clutch arm in slow areas on the course, the Rekluse clutch will allow me to leave the clutch lever alone and not have to worry about stalling.




I fitted a 13oz flywheel weight. I’ve always been a huge fan of the FWW on the RM and have always ran a 6oz and sometimes the 13oz for motocross. To further tame down the delivery a little I run an extra ¼-1/2 turn on the powervalve spring tension. This delays the opening and reduces the hit, which is perfect for the long enduro races.

I stripped the carb and changed the jetting a little. RM’s are rich from standard. I’ve gone with a 48 Pilot, NEDH needle in clip 3 and a 168 main to start with, going from previous experience this shouldn’t be too far out.

Finally I cleaned up and fitted a Boyesen Ignition Cover. This was originally the bronze colour, but was looking second hand so got it blasted up and then polished the letters

For the suspension I went ahead a bought a KYB ENZO factory fork and a virtually new standard KYB shock from an RMZ250, complete with Pro Circuit clamps. For Enduro use I plan on using the stock RM Showa forks with the new KYB shock. I really like the standard Showa RM shock and preferred to keep this for motocross. I will also use the KYB forks for MX as they are far too nice to hammer round rugged enduro tracks week in week out!




I tested the motocross set up before tear down and it works awesome. The KYB forks, paired with the 22.5mm offset clamps feel awesome and make for a calmer and more planted front end.




( * how the bike looked at the start of December, pre tear down * )


As anyone who has done so will know, MX valving for Enduro is brutal, so I had the stock RM forks and KYB shock revalved to suit. I worked with a good friend of mine who came up with valving stacks and spring rates the suit my weight and Enduro riding.


(mid valve stack)


(compression stack)

Good read... I love my RM’s

The frame guards and skid plate are like needles in a haystack! Nice find!

Nice build!

Thanks guys!
Still loads more to come. The bike is actually nearly finished, I just need to get round to writing it all up and sorting through the pics! Expect more updates soon.

Sixeightone: Tell me about it, I'e been trying to get my hands on the Light Speed stuff for ages with no luck. So I was super happy when I was able to get both in the same month! The only piece I still haven't been able to get is a carbon chain guide.... the search continues.

I just got a lightspeed chain guide, skid plate, transponder holder, and frame guards (250) for my rm125 build. My local shop ordered it from them and I got it within a week. Might be harder to get over there, not sure, but I didnt have any trouble at all.

Bman_145 wrote:

I just got a lightspeed chain guide, skid plate, transponder holder, and frame guards (250) for my rm125 build. My local shop ordered it from them and I got it within a week. Might be harder to get over there, not sure, but I didnt have any trouble at all.

What’d all that cost if you don’t mind me asking?

Next job was to get everything cleaned up and ready to fit. I scrubbed and picked the rads. Cleaned up the hoses and replaced a few dodgey hose clips. Cleaned and re greased the linkage and swingarm.

I did the Weston Beach Race on this bike late last year and as you can see below, everything got stained really bad. I used an alloy wheel cleaner and a quick rub over with fine scotchbrite to bring everything back to looking new (ish)

Cleaned and re built the rear brake assembly, fitted new stock Nissin pads and bled with fresh fluid. Finished off with black guards and clips from an RMZ and Ti bolts (including Ti caliper slide pin)

For the front brake I bought a Nissin system from a Honda. Smaller, lighter and more powerfull, this is a great mod for any Suzuki. I gave the brake a thorough clean, rebuilt it and bled with fresh fluid. Fitted a Renthal Intellilever. Red cap and aluminium banjo bolts (lockwired). Fitted new genuine Nissin pads. Finished off with Ti bar clamp bolts and Ti bolts to hold the caliper to the fork bracket. I will run an oversize disc but haven’t got one just yet.

Incredible build my man!

What year RMZ caliper guards fit on the RM? I like the black look.

b_kowalsk wrote:

What year RMZ caliper guards fit on the RM? I like the black look.

15-17 RMZ are black.
Same, so much better than the stock white which turns yellow/orange after half a season!

Sticking with the stock wheel set on this build, 19’’ rear and 21 front. An 18’’ rear would be ideal but I totted it up and it was going to be expensive so for the moment I’m sticking with a 19’’. I had the wheels stripped and hubs anodized a dark bronze/mag colour, as the wheels were fresh the original spokes and nipples were re-used.

I got a custom solid rear disc made by ABE, I mimicked the design used by the factory RM teams (Carmichael used a disc like this in the Anaheim 1 05 SX season opener). The solid disc should increase pad life and wet/muddy weather performance. For durability I fitted a steel RFX 51 tooth sprocket.

Finished off with Ti bolts, Ti chain adjusters, Ti axle nuts, Pro Circuit chain blocks, Metzler MC5 rear, Dunlop MX31 front and heavy duty tubes.


My RM wheels on the left, and fellow Vital MX member (and huge help with this build) 'Brunevals' 89 CR250 wheels

Brilliant build so far! Some nice ideas for my rm125

Out of interest did SFX do the wheels for you?? I am thinking of giving them a try, I want the bronze hub and yellow anodized rim

Headling wrote:

Brilliant build so far! Some nice ideas for my rm125

Out of interest did SFX do the wheels for you?? I am thinking of giving them a try, I want the bronze hub and yellow anodized rim

Cheers! Yep I used SFX. Quick turn around and good price, most importantly they did a really good job too. Would highly recommend.

Whilst researching MX to Enduro conversions online I came across the G2 Ergonomics Throttle Cam system. The kit comes with 3 cams, a 10% and 20% less pull cam (up to half throttle) and a stock cam. The RM motor is really abrupt, so I’m hoping the throttle cam system will smooth the delivery a little which should help in slow, technical and low grip situations.




Exhaust wise, for the moment I am going to use a Pro Circuit Works plated expansion chamber, with a Pro Carbon carbon guard, held on with new stainless clips. I may buy a Pro Circuit 2 or FMF Gnarly pipe later on if I feel I need more low end grunt.







For the silencer I’m going to test between stock and an FMF Q Pipe. I polished up the stock pipe a bit and finished it off with a brushed look.

Thanks for the info ref SFX wheels, will send my ones off shortly

Wow what a sweet find Russ! This is going to be an Enduro weapon for sure
Hubs look great

Cooper 688 wrote:

Wow what a sweet find Russ! This is going to be an Enduro weapon for sure
Hubs look great

Cheers Coops!
Not much more left to do now, pretty much just waiting on graphics. Hopefully sorted a set of Ti Pegs and braided hoses too.

My previous attempts at Enduros were seriously hampered by the stock tank. I had to pit twice in a 3 hour race as the stock 8 litre tank was only good for around 1 hours riding. I picked up a 2nd hand 12 litre tank of ebay for 25 quid, bargain! It was a little bit rough but I gave it a thorough scrub and it came up pretty well.
This should mean I only have to pit once now in a 3 hour event.

I ran the bike in at the weekend, pleased to say it all went well. Motor feels strong but smooth. The G2 cam and Rekluse make for awesome roll on power. You can leave the bike in 2nd, do a hairpin walking pace turn and just roll it on steady without touching the clutch.

Ran into a bit of an issue with the oversize tank though!
I was hoping to use the Pro Circuit clamps on the bike. However the rearward positioned fork clamp bolts came into contact with the tank and drastically reduced the turning radius of the bike.

The stock clamps however clear the tank fine, so I gave them a clean and rub over with scotchbrite, swapped the steel bolts out for Ti and mounted them up with the revavled stock forks. Also fitted a set of Pro Carbon fork wraps for added protection.

I removed the stock bar mount bolts and replaced them with titanium bolts. I fitted longer 70mm bolts which gives more thread overhang under the clamp.The extra thread means I can experiment with some aluminium bar risers I had made up. Currently using some +5mm risers, along with the standard RM bend Renthal FatBars.

One of a few Ti bolt orders.

I used Ebay seller 'T7design' for the titanium bolts for this build. I've bought from a couple different sellers now and T7design is by far the best. Very good quality bolt at a great price and fast postage. Would recommend.





Just waiting on graphics now!

The perks of being a CNC programmer...
I made these at work the other day. Clutch spring seating washers. This is a fantastic little mod that I had previously done to my RMZ450 with great success. A standard flat washer on the clutch spring allows the clutch spring to float around within the pressure plate. This means that the clutch springs go off center and rub the pressure plate, causing a poor feel at the lever.
These seating washers hold the spring central with no contact to the pressure plate. The difference in feel at the lever is very noticeable, much smoother and more fluid.




These are a rough set I made just to prove the program and check the size.

Another personal touch that I thought I'd share is my grip set up.
Start out with a Renthal Soft Full Waffle. I install them with the top waffle edge angled into the middle of the bike slightly. I then cut off the top portion of the waffle, essentially creating a 3/4 waffle grip.
I absolutely love this set up and run it on every bike I own. Loads more grip and fantastic in wet muddy conditions as well, great for Enduro.

The build is now practically finished.
My graphics turned up this week and look awesome. Iv'e gone for an all black theme. Having previously done a Carmichael Replica RM250 and a JGR inspired RMZ450, I decided to do something completely unique this time around.




Will get some completed photos this weekend!

Hey Russ, Whereabouts did you send your hubs to get coated?

The bike looks great! These things rip and i'm looking forward to seeing the end result.

Noantsinmypants wrote:

Hey Russ, Whereabouts did you send your hubs to get coated?

The bike looks great! These things rip and i'm looking forward to seeing the end result.

Thanks!
The hubs were done at SFX wheel, which are based in Wolverhampton, UK