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CR 125R starting problem
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Author:  GSjimmy [ Tue Jul 17, 2012 8:11 am ]
Post subject:  CR 125R starting problem
I have a CR125 that has been completely rebuilt and won't kick start. I can bump it and it will fire right off an runs like a champ. All of the electrical tests within range and the gounds appear to be fine. I did find a bent enrichment needle (choke/idle) that will be replaced tonight (PJ Flat slide carb) .

Motor - rebuilt upper & lower, new piston & ring, DG pipe, good compression, nice blue spark.

CDI & Stator are original, coil is aftermarket & tested fine. Couldn't find any pinched or burned wires. Coil to plug wire is an Accel 8mm yellow & has a new plug boot.

Gas is fresh 92 octane premium, non-ethanol blend @ 50:1 mix Spectra Gold.

I have not tried a few drops of fuel down the head yet, so this may be a carb thing if the bike starts like that. So right now I have a bike that is very stubborn on starting with the kicker, but runs fine if I bump it. I'm just a bit stumped here!

Jim
Author:  GSjimmy [ Thu Jul 19, 2012 10:56 am ]
Post subject:  Re: CR 125R starting problem
I ordered a new enrichment valve and coil. Installed the valve last night, still a no start on the kicker :( . The new coil should be here on Friday, so let's hope that this is the thing it needs.

My son informed me that the coil tested bad (coulda told me 2 weeks ago!) Must be at the upper limit for resistance as the bike does run if bumped. My best guess is the spark is not hot enough to lite the bike when kicked. But if the motor spins faster/longer (bump start) then she fires up.

Anyone else have any ideas?
Author:  GSjimmy [ Mon Jul 23, 2012 8:15 am ]
Post subject:  Re: CR 125R starting problem
Well we are back to the same problem. But I now have more of an idea what may have failed. I replaced the coil & enrichment vavle. Still had to bump start to get going. But I had a new “interesting” thing pop up when I had this bike out around the back yard.

When coming off the pipe down to an idle, the bike would die. It has done this a few times now. So I tore down the top of the bike and checked for spark. Nothing when just the kicker is used. I also tried the WD-40 trick, & still a no start (Thanks Jon). So, since the bike has sat for 15 years or so, I'd have to assume that the inition has gotten weak at slow rpm.

The coil, Boyesen Reeds, and cleaning have made starting and running somewhat easier, but I have to have it start with the kicker. Kinda sucks to be this close and yet not be able to trail ride the bike.

Jim
Author:  GSjimmy [ Mon Jul 30, 2012 7:42 am ]
Post subject:  Re: CR 125R starting problem
Think I found the problem with the 125! Have a busted stator plate at the Optical pick-up. Kinda flattened out the bump on the flywheel and has ground down the pick up some. I have a bunch of parts that should be here today to fix this issue. Anyone else have anything like this happen?
Author:  GSjimmy [ Tue Jul 31, 2012 7:25 am ]
Post subject:  Re: CR 125R starting problem
I manged to fix the problem last night! A big thanks to all that have helped with this project, Chris Halverson, Jon Mikkelson, Mark @ MP, TJ Richard Fogel and Mark McWiggen "Wiggy".

Heres the deal, it was quite a combination of of broken items: broken kill switch, broken stator plate, bad optical, nearly broken stator wires, bad reeds, bad choke pull. Replaced all of this "stuff" and she fired up on about 1/2 a kick! So no more bumping it to get going.

Other items that were done on this one: repainted/rebuilt the frame, found the missing front plate, new Renthal bars & Scott grips, cleaned up all the other plastics, new to me DG pipe, rebuilt engine & carb, new to me rear shock (thanks Jeremy in OK). Of course it still should get some new tires, but these should last awhile with the boys learning to ride.
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