My new 1987 RM 125

cpracing519
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132
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Jenison, MI US
9/16/2009 8:07pm Edited Date/Time 1/27/2012 3:18pm

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Pat327
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CA US
9/17/2009 12:09am
Sweet, man. Are you going to restore it?
cpracing519
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Jenison, MI US
9/17/2009 4:48am
Oh yeah! this winter I will tear it down and get the frame and engine powder coated and then find new plastics/graphics. i'm going to try to get it back to oem specs as possible. Plus I will be racing it also for 2010! I cant wait to get it finished. Now I need to find some JT Racing gear!
Wandell
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Cairo, GA US
9/17/2009 6:02am
Sweet!
lumpy790
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York, SC US
9/17/2009 7:37am
Didnt the Bomber wear Fox?

The Shop

kawboy388
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Covington, TX US
9/17/2009 7:56am
Almost all the rider's on the 87 team wore FOX, Turpin,Tichenor,Schmit, DeVane. O'neal for Kehoe, Hallman for Holland.
ThePipe
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1836
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Hell WI pop 1, WI US
9/17/2009 6:55pm
Great bike!
I had one last Summer 08
Check the far right side of the crank for wear.
The crank doubles as the waterpump shaft and loves to groove. All the new waterpump seals in the world won't fix it.

If it's grooved, weld it and then turn it down on a lathe.
Trust me, It will be easier to do that than find a good crank.
90rm125
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122
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Location
Clarks Summit, PA US
9/18/2009 8:44pm
nice ive got a 1990 rm125 that I am in the process of restoring but college keeps getting in the way of ever finishing it
MXVet261
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711
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4/1/2008
Location
Valley City, OH US
Fantasy
3973rd
9/19/2009 8:56pm
Can't have enough old RM's!

My first "old" bike pickup was a '87 RM250. Really fun bike to ride.
leeroy
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150
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6/14/2007
Location
corona, CA US
9/20/2009 9:06pm Edited Date/Time 9/20/2009 9:07pm
here is a pic of my 82 that i found back in april. i have took it apart and am about 3/4 way through restoring it.....sorry i am having trouble uploading the pic !!!
cpracing519
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132
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8/27/2009
Location
Jenison, MI US
9/22/2009 7:21pm
Ok, finally got it to run decent after carb work, reeds, and air screw adjustment. Now I need to put new gas in it and oil. I havent had A 2 stroker in many years, help me out! What mixture would you recomend in the gas 32:1? Oil in the tranny says 20w40 motor oil according to the Clymer book? I've been told ford atf and honda 80w gear oil? ATF sounds to week and 80w sounds to thick. Should I just use 20w40?
Thanks ahead of time! I want to race it this weekend!
motogeeze
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Orleans FR
9/23/2009 8:29am
You can really open up a can of worms when you start talking oil and what kinds, everyone seems to have a different setup/opinion. I run 40:1 in my vintage bikes and have for ages... I use Champion WP ( formerly Duralube , available at most KTM dealers) but most any of the major brand mix's are fine, Yamalube, Maxima, Golden Spctro etc etc, ,some oils say you can go with a 50:1 ration and some like amsoil claim 100:1 but no way Id ever run it that lean. I know back in the day some manufacturers called for 20:1 ratio's but the oils then werent as advanced as the available synthetic mixtures these days. Personally I wouldnt recomend an automotive oil for the trans as they dont contain the anti shear additives a good tranny oil needs and have friction modifiers that can cause clutch slippage but you can use them in a pinch if you have too. If your going to run something of that nature Id use a good diesel oil , Shell Rottela synthetic works well and is available at most Auto Zone parts stores and Wal Mart. While priceier the motorcycle specific motor oils do contain the additives for clutch and transmission protection and any of the transmission specific ones should work well. The only issue I ever had was with the Bel Ray gear saver which caused the clutch slippage in the Maico's and KTM's we used it in. ATF has great anti shear/foaming properties but its viscosity is a worrisome point to me especially in hot weather conditions, that being said gear oil viscosity ratings and motor oil viscosity ratings are different, so an 80w gear oil wouldnt have the same viscoscity as an 80 w motor oil. Heres a nice little newsletter from Maxima that shows the way viscoscity index's work:http://www.maximausa.com/technical/lubenews/spring98.pdf
cpracing519
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Jenison, MI US
9/23/2009 8:52am
Thanks Motogeeze, that helps out a lot! I will try mixing it at 40:1 and then go from there!
CamP
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Colleyville, TX US
9/23/2009 9:37am Edited Date/Time 9/23/2009 9:47am
Thanks Motogeeze, that helps out a lot! I will try mixing it at 40:1 and then go from there!
In a 125, you should run no higher than 32:1. contrary to popular belief, more oil in the fuel produces more horsepower. The theory is that it improves ring seal but in practice it makes more power on he dyno and decreases blow-by and piston wear. In fact, I'm running 28:1 with 100LL in my RM250 and the exhaust produces zero spooge and a perfect grey exhaust color in the silencer.

For a good premix oil that is easy to find and priced right, try Lucas semi-synthetic. You can buy it 7 days a week at any O'Reilly or Autozone auto parts store for just $5.99 a quart.

The Shell Rotella T 15w40 holds up to the meshing tranny gears better than their 5w40 synthetic. It's cheaper also.
cpracing519
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132
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8/27/2009
Location
Jenison, MI US
9/28/2009 6:58pm
Racing was fun, but my 2nd moto I realized that my bike still runs like crap. Oh well, now its time to dismantle it and start the restore.
Question on graphics? Dont need them yet, cause thats the last thing I need to do, but just trying to find info on my bike.
The vin on my bike says its a 1987. Code H
1. Is it suppose to have Full Floater on the swing arm or Suzuki? Mine says Suzuki.
2. On the radiator shrouds are they suppose to say RM125 or just RM? Mine just says RM.
I've been looking at other pictures online and havent been able to figure out what I need yet. Any help would be appreciated!
Looking at buying another 87 RM125 Tuesday to buy for a parts bike, but it doesnt have any graphics on it to compare to mine.
CamP
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Colleyville, TX US
9/28/2009 7:27pm
cpracing519
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Jenison, MI US
9/28/2009 7:35pm
ha, that kinda answers everything! I havent come across an original add yet, Thanks!
cpracing519
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132
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Jenison, MI US
9/29/2009 5:52pm
Just picked up this 87 RM 125 for $300!

Pat327
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CA US
9/29/2009 6:07pm Edited Date/Time 9/29/2009 6:16pm
I know pictures can be deceiving, but the #311 one looks like it's in better shape. I would take both apart and look at them carefully before you commit to one over the other (as far as major parts go I guess is what I'm trying to say). Like, you might get one frame powder coated and then find a crack or something like that when it's done for example. That said, I love these old bikes! For less than 1K, you can have so much fun it's unbelievable.
CamP
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6828
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Colleyville, TX US
9/29/2009 7:27pm
Yeah, the 311 looks good and $300 is a steal even if it doesn't run.
90rm125
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122
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Location
Clarks Summit, PA US
9/29/2009 7:52pm
I got my 90 for $200 but it also didnt have a topend,exhaust,and the bottom end was seized
cpracing519
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132
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8/27/2009
Location
Jenison, MI US
9/29/2009 7:59pm
I agree, the 311 has some better stuff(plastics) on it. Plus it has alot more oem items on it. Hopefully I can get them both running in top shape again. I think I might totally restore 1 with all new stuff for a race bike and then fix 1 up for a practice bike. Not real sure yet, time will tell when I get them torn down! Its going to be a fun winter!
cpracing519
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132
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8/27/2009
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Jenison, MI US
10/29/2009 6:20pm Edited Date/Time 10/29/2009 6:24pm
here's my slow progress due to cold weather here in Michigan. Both are torn down and now going through the motors. I just tore the top ends apart and need to figure out the bore on both.

So far 1 motor had a ton of dirt in it from a torn reed cage boot, plus it had a stock piston in it with a bored out cylinder. You would think the person would have put the correct piston in it after borring it out. The other motor looks pretty good. Both cranks/rods appear to be in good shape. Looks like I only need to do top ends on them.

What is the best way to flush out the bottom end with out splitting the cases? Can I just hose them out with water or should I use a engine degreaser or mineral spirits?
How bout painting the frame/motor? Powder coat or paint?


Wandell
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Location
Cairo, GA US
10/29/2009 7:31pm
Powdercoating would be better for sue.
cpracing519
Posts
132
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8/27/2009
Location
Jenison, MI US
12/22/2009 4:47pm Edited Date/Time 12/22/2009 5:16pm
Finally sending out the frames to the powdercoater! Now I have a few questions concerning motors.

Are the 87 motors and 88 motors basicley the same. I have a ton of 88 motor parts, but own 2 87's.

Can I put a 88 jug,cylinder, and piston onto my 87 motor? I have a modded jug that is borred over from an 88 with the correct oem piston. I want to use it on my 87 motor. Looking at everything they seem to be the same, but I dont want to put it all together and then blow it up right away.
90rm125
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122
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7/15/2009
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Clarks Summit, PA US
12/22/2009 7:05pm
the 87 and 88 cylinders have matching part numbers so they should work. I know the 89-91 motors are the same.
12/23/2009 6:59am Edited Date/Time 4/17/2016 7:35pm
Try going to NAPA and get a quart of engine flush, then once you flush it out use pre-mix gas & oil to flush again so you have some oil mix on the main bearings and rod bearings.
cpracing519
Posts
132
Joined
8/27/2009
Location
Jenison, MI US
12/23/2009 7:51am
Just dropped off both frames to the powdercoater! So far I have checked and compared both year stuff and they all appear to be the same, so I will use them. I will have to try the engine flush stuff also. Thank you all for the help, I really appreciate it! I will post more pictures when I get the frames back!
cpracing519
Posts
132
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8/27/2009
Location
Jenison, MI US
12/31/2009 8:08pm
more questions again. My 87's came with a 18 inch rear wheel and a 21 inch front(drum brakes rear and disc fronts). I want some gold wheels or maybe just rims and get them re-spoked. anybody know what years fit or if I can use a Honda/Yamaha/Kawasaki etc. wheels. Maybe also looking to put a 19 inch wheel on the rear on 1 of them and converting it to disc brakes. Thats a whole different thing to look into later on though!

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