RM125B rebuild pics

[John Orchard]

Well I recently started work on my RM125B project that I picked up ages ago from Discount Motorcycle Wreckers in Coburg (Vic).  I didn't test ride it; just heard the engine run for about 30 seconds and that's it.

The following pics are as I picked it up except it had a white YZ125G fuel tank and a shitty blue, home job seat cover.  Sorry about the light reflection on the camera.





The bike looked like it had been sitting outside for all of its 35 years and in a sad state of repair BUT BUT BUT upon tearing it down I find less wear on the bike than my 2 year old YZ250!! how/why?  The rear shocks still had gas, damped and didn't leak oil! The clutch basket fingers did NOT have any wear grooves from the fibre clutch plates!  AND the footpeg pins were not worn and the pegs did not droop!

I think the reason it had little use is because of a manufacturing fault in the gearshift mechanism; the tang that resides between the gearshift return spring was not contacting the arm of the spring that returns the shifter to the central position after an upshift; this would have been a prick to ride, with only vibration allowing the gearlever to return to the central position, I'm sure this would have been very hit & miss.

Anyways, I've started the rebuild, it is a build to get it ready to ride; not a restore job.  More picks to follow soon.

[maico police]

Looks like a good pick up John. Looks to be pretty complete. Seat and tank wouldn't be much of a drama I'd think. Good to see it isn't going to be a garage (drama) queen. Nice one.

[John Orchard]

List of new parts just purchased, some on evilbay at cheap prices, some from Raceway suzuki (Keilor, Vic) still at cheap prices; in fact most parts I order from the Suz dealer are cheaper than ebay and comes in the same day!

NEW PARTS
- Wiseco piston, rings, pin & s/e brg.
- Crank bearings & seals.
- Rod kit (to keep as a spare).
- Boyeson reeds.
- airbox-carb joint.
- Fork seals.
- Fork wipers.
- Front & rear wheel bearings.
- Needle roller swingarm bearings.
- Throttle cable.
- Rear brake cable.
- Clutch cable.
- Tank cap.
- OEM airfilter.
- Fuel tank straps.
- RM125X front number plate (square).
- Seat sponge & cover.
- Handlebars (gloss deglazed to satin black).
- 428 X-ring chain in gold.
- 14/59 sprockets, alloy PBI rear with mud channel gooves added.
- Chain tensioner plate, spring, bushes & rollers.
- Aftermarket front (Tony D rep) & rear guards.
- NOS side covers.
- Old school (5x4) 4.00 x 18 Mitroc Fortune rear tyre.
- Front brake cable guide.
- Original replica throttle assy.
- Kill switch.

USED PARTS
- Optional alloy swingarm.
- Cylinder (freshly bored) 1.5mm o/s with brand new Wiseco piston & rings.
- Fuel tank.
- Alloy muffler.
- RM250B rear shocks - for the springs and to cut up to study internals.
- How to win motocross book 1974 (just to get me back in the groove).
- Motorcycle tuning for performance book 1974 (just so I know how to work on it lol).
- Front tyre.
- VM34 carb.
- Ignition coil.

That chap at Discount Motorcycle Wreckers has a lot to answer for,  getting me hooked on this rebuild!! LOL  ;-)

[John Orchard]

Rear wheel .... PBI alloy rear sprocket with mud channel grooves, optional alloy swingarm, X-ring chain, 5x4 retro knobby, new tensioner, best mod is the rear sprocket bolts replaced with studs; no more chopped-out rear hub or stripped threads.

[John Orchard]

Ran it thru the gears for the first time on the weekend; I forgot how flexy those skinny axle/swingarm pivots are lol.



Note modern MX stand; didn't need to be elevated to support the bike  :-)



The alloy muffler I found off a go-kart at the tip, welded-on footpeg wideners, 34 mil carb just needed one size up on the pilot & main, the new, original RM125B handgrips cost me $7 for the pair from Tailand.

[Nipper]

Well done John, your work on the bike is fantastic, I hope the RM 125 I am working on will eventually come up like that !

[PERM250]

Great job john nice to see another rm come back to life like your work.

[John Orchard]

Thanks Guys, I appreciate your comments.

[John Orchard]

Thanks :-D  I find myself just sitting in the shed staring at it; god I'm 17 again  ;-)

[mr77rm]

Where did you get the plastics from ?

[John Orchard]

I got the whole lot from www.vintage-suzuki.com

[John Orchard]

Wins 2013 Australian Championship 

[Ted]

Good work John. I commented just after I got the bike from you how good it was, triggering an almighty shit fight RE alloy arm...haha

Changes : New Ohlins piggybacks, TEKNIK fork mods, slight mod to new GMC pipe, new GMC muffler, drilled and replaced all bolts to stiffen everything up, new Pro Taper bars, new Domino 1/4 turn throttle, new cables, new jetting specs, port mods,

It was the perfect base that just needed a bit more coin chucked at it. You wanna buy it back? You can have it for five figures

Thanks mate