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Only $10 for all 2026 SX, MX, and SMX series.
That other 465/500 well, they've taken a deposit on it. Rather gutted. Im buying a completely new crank, con-rod kit and piston for this one.
Oh wow haha. Isn't that the way it goes? Shoot. Well, hopefully you can find another. Although, you may not need it since yours is coming along so well.
It would've been cool to keep hold of for a year or two and then i could restore it. This little 81 RM100 will be a cool little bike to restore. Parts are much easier to find and are far cheaper to buy. I want a few old bikes i can keep on the back burner.
I've got 2 pan head screws coming for the boot clamps. Ive fitted the brake and clutch cables. The brake lever adjuster didn't fit the end of the cable, it was too small so I used a wider one. The new numberplate doesnt fit either.
The Shop
Luxon 4-Post Bar Mounts
$189.95 - $239.95
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Work to do, buy and pay for..
Barrel/jug... repaired and restored.
Buy carburetor.
Engine parts, screws, washers, seals etc.
Frame repair/paint.
Con-rod kit including bearings and fitting.
Rear shock cerakoated.
Side panels.
Air-box and filters.
Restore inner rear fender rubber.
Re-paint bell-crank.
Buy main drive gear bearing and tank mount cushion.
Wow, I didn’t know they made an RM100. I guess they were competing with the YZ100. Interesting 😎
Just ground out the rust and crap from inside the hub as the brake shoes wouldn't even go in. All works ok now.
1981 RM100...
I got the right side of the crank today from CMSNL. I was lucky because there was only 1 left. I'll get the left side next week. With what i swap out i should be able to part build another engine. Ive also seen another left side casing for sale.
Does anyone know the best thing i can put into a ceased cylinder prior to attempting to free it up?
50/50 mix of ATF and acetone as shown in the link below. In the USA, the old timers here use a product called "Marvel Mystery Oil" (it works reasonably well). I use "Kroil" and it works very well. A friend uses citric acid but I think that's a bit harsh. Good luck!
https://www.garagejournal.com/forum/threads/homemade-penetrating-oil-te…
Eric
Cheers Eric, would diesel oil work? I'll have to look into that Kroll. Its for that ltitle RM100 higher up. Its selecting gears but its ceased you see. Its probably in need of a rebore, piston and ring.
I don't believe the diesel oil would work as I understand you need something more along the lines of a hydraulic fluid vs a lubricating oil. So, I would stick with an automatic transmission oil/acetone mix. I have also heard that brake fluid/acetone mix works well in a pinch (read this in Machinist Magazine many years ago).
Eric
Looking great! Nice job!
What's best, remove the head?
Cheers mate.
If you get the aerosol version of Kroil, just spray it down the spark plug hole...Removing the head would be the best way so you could see the orientation of the piston to the ports so you can maybe block it from running out the ports too much!
New crank half arrived today. The other half in a week or so along with the new con-rod kit. Ill be getting a new piston when the cylinder has been repaired.
Pit Row
Nice 👍
It’s crazy that it has two crank halves
Hi guys, when i got the doner engine i got a spare cylinder head with it but its not a 465, its not a 500 either i think. The head bolt holes are far closer into the centre. Its roughly the same size but fins are smaller. Have you any idea what its from?
There's a series of numbers and letters on the underside of the head saying either 1S-ZZ-417 or 1977-427 or 13-ZZ-417. I cant quite work out what they are.
I think ive found it. It looks like an RM250 althoigh im unsure on the year.
Still cant work out what year it is. When it came from Huggys they thought is was from an RM500.
Located an original 38 flatslide ss carb so ill be grabbing that next week along with the other NOS crank half. I want the barrel replated if possible to allow for an original standard piston and rings. Im buying a new piston, con-rod and pin, and piston pins and bearings. If anone knows of a NOS 465 Cylinder/jug or one in very good condition, please let me know. Im also in need of a very nice airbox. Ill pay up to £150 for a mint one.
it is not a plated barrel, cast iron liner.
Hi PHill,
I thought they could be be plated to reduce the play in the cylinder? I know they can be rebored. Ive located an undamaged clunch basked and also a flatslide carb from Huggys, only there's no float bowl, although they do have a couple of those for sale. Now i have found an undameged jug and piston for sale so i may end up selling the pile of crap ive got and swapping it over. Ive got the crank, jug and clunch lined up so its just the carb and airbox to sort out. The gear selector rod is also bent so that needs addressing aswel. This enine was a total fkn bin.
You can only Nikasil aluminium cylinders, not ones with a liner .
You can plate them slightly thicker to match a piston, but i will say i dont recall any air cooled bikes that had Nikasil cylinders, it came in as bikes went liquid cooled.
74 YZ 250 had a chrome bore I believe and 78-79 CR 250 had chrome or Nikasil.
Just got the brand new left side crank. Paid for this complete new crank set-up with old BMX and motorbike parts. Ive located a fresh, undamaged cylinder/jug so ill be selling this damaged one for spares or repair along with 2 casings and a cylinder head. Ive made £350 aleady.
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