1980 RM125 Project

Looking to make this a solid race bike.  It runs good and doesn't seem to be as worn out as it looks, which is a plus. 


I know zero about these bikes, trying to get as much info as possible, mainly on suspension mods and setup.  Need a shop manual.


Right off the bat, I see the torque link, rear brake adjuster look wrong.  The link is home made and the adjuster rod seems too short.  Also, the chain guide is missing some pieces, anyone know of an aftermarket replacement or a new model that fits?


Silencer options?  Would like something serviceable.



Jemco/dg pipe,dg head, fox air shocks. These were great bikes for their time and everyone I knew had one. The only problem is the 81 rm125. With that glorious "Full Floater" rear and liquid cooling, modern ergo's, the 80 model had a short shelf life. I had an 80 rm125 in 86, zero bottom end power/screaming top end. I was 165lbs at the time and could bottom the stock suspension pretty easy. As you know, those stock shocks are long gone, I dont see anyone rebuilding them. I see almost all racers use the works shocks, most restomod guys shoot for fox airs. Front forks are workable with springs (works, I think) and respond well to oil level tuning.

Edited by ickfinger

Cool, thanks!  That's the kind of info I was looking for.  I did a quick search on Ebay for rear shocks, I guess I find them by length?


Here's some more photos.  I've just been lubing the cables making sure the controls work properly, replacing hardware, etc.  I straightened out the bars, sanded and painted them.  cleaned out the (aftermarket?) throttle, etc.  


Not one ding in the pipe. Plastics are all Made in Japan.



















The made in sweden throttle assembly is probably a Gunnar Gasser unit. The stock throttle cable sticks up out of the case like a boner and looks wierd, then is routed thru gthe stock #plate. Back in the day, shocks were measured eye to eye length. Those are modernish levers, as the stockers were looong levers, leftover from the 70's.

The shocks are supposed to be rebuildable with 4 way damping adjustable Works Performance shocks will make life easy . Race Tech can totally dial in the forks if you are going to race it. Most of the parts for the chain guide are still in Suzuki parts fiches. It's way better than what was used on the 79. The 79 had a lighter crank so it wound up a little quicker than the 80. Make sure the chrome is good on the forks and shock shafts if you want to rebuild them. It seems like the Suzuki chrome is thinner than all the Yamaha stuff I've seen and have seen a lot of both. Have fun with it, it looks like you have a real good start for a resto. 

Thanks for the info.  About the shocks, I can't find an adjustment anywhere and the dampers are welded.  Luckily they seem to have good damping (for now).  They'll probably leak like a sieve after I ride it a bit.  I was able to fab up the parts I needed.  The case saver is 1/4" aluminum plate, the brake stay is 1/4" alu. flat and the chain guide is 1x1" hdpe, only cost like $6 bucks for 2 feet of it.



Looking good! I might recommend clearancing the case saver a little bit more.The slightest foreign object can jam in there and wreak havok. At best mud will jam in there easily and accelerate chain wear! Anxious to see it with polished plastics!

I was all set to take it out for a ride last weekend, just needed to do the air filter and change the trans oil.  I go to remove the air filter and it comes out in pieces. DOH!  Needless to say, no riding....but I do have a new filter coming along with some fork seals.


I didn't have the patience to polish the side covers.  I sanded and scraped with a razor but it seems like if there was any good plastic there I would really have to remove alot of surface material.  F-that.  I got a can of paint.  If all goes well I may buy some new pla$tics for it.  It's a decent 10 foot'er now.  lol  


I got everything else fixed up, adjusted, lubed, etc.  New tires too.  



Waiting for parts....


made a chain roller, cleaned and refinished the shocks, greased the swingarm pivot and changed the fork oil.  











Edited by Jeekinz

Worked out most of the wrinkles, got it mechanically "solid" rider.  




Did a EVO class race, need to address the power output.



Did you paint or powder coat the shock springs? If paint what kind did you use, are you worried about the paint cracking?



I painted the springs and side panels with Valspar paint from Lowes.  The springs still had the original paint on them, looked horrible.  So I just cleaned them up and sprayed.  I'm not concerned about chipping or anything as it's a rider. I already have one carpet cruiser, riding is more fun.

I had a 79 rm125 that i painted the springs with rustoleum rattle can, did not chip, even after hammering whoops!

I had a 79 rm125 that i painted the springs with rustoleum rattle can, did not chip, even after hammering whoops!

Cool, I'll give it a try then, just scored a used set of Ohlins piggybacks and I need the springs to be yellow....paint it is!  Worst case I can repaint them if they chip



The Valspar I used is a great match for the Suzukis.

Oddly enough, I see this RM has migrated to Nassau County, L.I.N.Y., and is up for sale on CL!

Yup. I figured thats where it would wind up. At least I saved it. Just hope someone rides it.

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