1979 RM125

First things first , drop kick the original fenders if you have them and replace them with 1980 plastic...lol. j/k Hopefully Newman will chime in. How about some pics of your bike.

Take some time and look back through this forum. There are a few threads on it.

Vintage Suzuki has a lot of parts for these. Surprisingly, there are a lot of OEM parts still available. Great turning bike. I used a DG swingarm and Ohlin's shockss. I did, as suggested, use the 80 style fenders.

Bike has been stone reliable and good enough to win. It is at a severe handicap with me at the controls!!!

Here's a little trick:
1. Install a 0.5 head gasket (p/n# 11141-40701)..Stock is 1.0
2. Install (2) cylinder base gaskets (p/n#11241-40200)
3. Rotate magneto stator plate counterclock-wise 2.mm (0.079 in.). This retards ignition 2 degrees
4. Install a 14 tooth countershaft sprocket .
5. Add a 34mm carb

I think that was the RM that has a black wire coming off the CDI. That is a rev limiter. You can clip that if you really want your bike to sing.
How did those mods help the power Craze? It sounds exactly what that bike needed. I liked the motor on my friends 78 Rm more than my 79. I was such a skinny little squid back then.

What about the 520 chain conversion? Looking back 35 years at a 21hp bike, is it necessary?

If you remeber that Al you probably remeber Suzuki changed from 428 to 520 on the 1980 which was basically the same bike. I would definatly run a good quality 428 chain.
If you have the engine apart, get a counter shaft from the 78. They were solid. The 79 was hollow. I've seen 3 broken 79 countershafts that had correct chain slack.
Same with the clutch arm that pulls the pressure plate out. Teeth would break on the 79. 78 arm fits exact and is steel.

Motor wise, the biggest difference between the 79 & 80 motor is the crank....Suzuki went with a heavier crank in 1980...I haven't broken in the motor yet, but I'm going to see how much of a difference the mods make.....I have (2) each of the 79 & 80 motors, so will see.

I've got a 79 RM125 and it screams!

I would say yes but only if you were going to trick it out with Works shocks and translucent side covers, aftermarket pipe.

I just picked up a 1980.

I'm digging that bike. Love the original style plastics and graphics. Thats what 1979 was all about.... an completely different look.

That bike looks in great condition X, good score! Hope you didnt use the "new TV" money to pay for it.

Still working on mine
I have lots of parts now and another complete parts bike
Kyle

Her ya got right from the Suzuki tech bulletin RM-44

I had an '80 for a little while. Chassis was pretty decent but the engine was lacking for some reason. I could never get used to the shocks pushing into my calves and sold it.