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Author Topic: PROJECT: 1979 RM125  (Read 18571 times)

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Offline motoxr377

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PROJECT: 1979 RM125
« Reply #15 on: August 20, 2012, 03:01:58 AM »
Ok Coop here's a special update just for you! Got the cylinder and head back from Eric. He did a good job. I still need to set ring end gap for the Wiseco, and the bottom end is getting there slowly, but I thought I'd show off some of his work. I just painted the cylinder in Semi-Gloss. Turned out alright, but still have to redo the finish on the head.  I have never had anything anodized though, and am worried about polishing it and who to send it to.  I want it to look right, though. Suggestions?

I found this magazine cover the other day... Premature Burial? :o


Here's some shots of the painted, ported, bored, and honed cylinder.



The chamber was polished up a ton from before, with only slight pitting remaining. It looked pretty bad before this.


Eric had specs on hand for this bike. From the looks of it he didn't touch the transfers if any, but the exhaust port has been heavily modified in both height and width. The intake and exhaust runners have also been honed and the ports are much smoother at the bridges. Good work, excellent price.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline cnrcpla

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PROJECT: 1979 RM125
« Reply #16 on: August 21, 2012, 02:05:27 AM »
That engine is going to look pretty sharp with that black and gold  :o
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline citabjockey

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PROJECT: 1979 RM125
« Reply #17 on: September 05, 2012, 05:33:52 AM »
IIRC, the tests back in the day were split -- some said the bike was ahead of its time and great -- others thought it missed the mark (and those were in the minority). I don't remember that article specifically. The tag line could be because they didn't like the 'C' model? Don't know.  :<img src=" title="Roll Eyes" class="smiley">


I found this magazine cover the other day... Premature Burial? :o


« Last Edit: December 31, 1969, 04:00:00 PM by ' »
Yamaha CT3, RT3, MX125, SC500, Toy Prius, Diesel F250 (it all balances out)

Offline _X_

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PROJECT: 1979 RM125
« Reply #18 on: September 07, 2012, 01:27:17 AM »
is that rogers dent in bob's pipe?HA!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline motoxr377

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PROJECT: 1979 RM125
« Reply #19 on: October 09, 2012, 04:08:57 AM »
Lots of parts on order! I've got a YZ that's getting wrenched on right now. I hate juggling projects.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline motoxr377

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PROJECT: 1979 RM125
« Reply #20 on: October 28, 2012, 01:36:17 AM »
Update!

Cylinder is ready to go, bottom end is not.  Ring end gap is set.  Painted, Ported, Bored and Honed (with exhaust bridge relief!) Cylinder is now mated up to the refinished DG Sunburst Head.  I chose to paint it, and it came out great.  If anyone is interested, it is VHT Metalflake Gold Engine Enamel, and is available at AutoZone.

5 coats later:


Also, I found a picture of the bike when I brought it home for a case of BL (note: now parted with '01 RM125)


Stay tuned!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline TMKIWI

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PROJECT: 1979 RM125
« Reply #21 on: October 28, 2012, 08:15:53 AM »
The head looks good. 8)
« Last Edit: December 31, 1969, 04:00:00 PM by ' »
If you don't fall off you are not going hard enough

Offline Super Trucker

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PROJECT: 1979 RM125
« Reply #22 on: October 28, 2012, 04:46:30 PM »
Cool project  I remember seeing all the 79 rm,s at the dealership in 79. I wanted a 79 rm80 real bad. At 12  I was a little big for the 80, but the 100 was too big and a 125 looked huge. McGrath,s 1st mx bike was a used 79 rm80. The decal kit really made the 79 rm,s pop.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline motoxr377

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PROJECT: 1979 RM125
« Reply #23 on: February 01, 2013, 11:00:46 PM »
Update coming tonight!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline evo550

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PROJECT: 1979 RM125
« Reply #24 on: February 01, 2013, 11:57:12 PM »
Some piggy back Ohlins would be trick. ;D

only kind of shocks that need to be on a vintage bike are the fox floaters. but then again they're impossible to find, but if you can find them, fox shocks are the way to go. But if you cant then ohlins should be pretty good too  ;D
What shocks are fox "floaters" ? Never heard of them.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline 2T Institute

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PROJECT: 1979 RM125
« Reply #25 on: February 02, 2013, 02:56:43 AM »
Update!

Cylinder is ready to go, bottom end is not.  Ring end gap is set.  Painted, Ported, Bored and Honed (with exhaust bridge relief!) Cylinder is now mated up to the refinished DG Sunburst Head.  I chose to paint it, and it came out great.  If anyone is interested, it is VHT Metalflake Gold Engine Enamel, and is available at AutoZone.

5 coats later:


Also, I found a picture of the bike when I brought it home for a case of BL (note: now parted with '01 RM125)


Stay tuned!

That head is great way to loose a few HP
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline motoxr377

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PROJECT: 1979 RM125
« Reply #26 on: February 02, 2013, 12:42:45 PM »

That head is great way to loose a few HP

Elaborate. Eric set the squish, it has higher compression, other than that it is identical to a stocker.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline _X_

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PROJECT: 1979 RM125
« Reply #27 on: February 02, 2013, 01:17:24 PM »
motorxr, whats it really matter? its a vintage racer and i'm sure it will draw alot of attention at the track. not only that, the majority of vintage racers are slow.HA!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline motoxr377

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PROJECT: 1979 RM125
« Reply #28 on: February 02, 2013, 01:36:50 PM »
motorxr, whats it really matter? its a vintage racer and i'm sure it will draw alot of attention at the track. not only that, the majority of vintage racers are slow.HA!

Thanks racer x.  That's what I'm going for.  The bike's for Unadilla MX Rewind, after that I'm not too sure what I'll do with it.


Engine's complete, just waiting to be ridden.  55.5mm bore, Boyesen reeds with matched intake, ported by EG, head mods by EG. The kickstarter is a superseded part.





I just need to blast and coat the frame black, send out the front boingers and get rear ones built.  Also, I'm waiting on swingarm bearings, a pipe, rubber pieces, seat foam,etc.

The bike's getting a 520 conversion, made easy by the 1980 model.  I just picked up some Pro-form pegs as my feet are huge and the stockers are not. They fit perfectly. Compared to stock:


Stay tuned!
« Last Edit: December 31, 1969, 04:00:00 PM by ' »

Offline SachsGS

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PROJECT: 1979 RM125
« Reply #29 on: February 03, 2013, 01:03:11 AM »
Fox floaters use air instead of a spring. I've got an old set of Fox piggy back coil spring shocks on an 81 Wheel smith 250 Maico and they work very well.
« Last Edit: December 31, 1969, 04:00:00 PM by ' »