OzVMX Forum

Clubroom => Tech Talk => Topic started by: jawa76 on March 06, 2011, 08:22:26 am

Title: Honda CR125 r
Post by: jawa76 on March 06, 2011, 08:22:26 am
Ok I've officially put up the white flag.
I have just accquired a 1984 cr 125, BUT it is a absolute mother to start.
Thats not to say the bike dosnt run, it does and sounds fine when it is running.
But getting to that point is hurrendous.
I have done all the regular stuff.
1. Checked fuel flow.
2. Cleaned carb and checked settings.
3. Checked ignition timing. (With a dial gauge and cyl head off). Spark is strong
4. Checked reed block petals.
All is as per mister Honda says it should be.
Is there anyone out there with a idea ?
This bike is destined for the back of the shed.
Steve.
 :(
Title: Re: Honda CR125 r
Post by: mainline on March 06, 2011, 11:36:50 am
leaky gasket somewhere? head maybe?
Title: Re: Honda CR125 r
Post by: ELC hunter on March 06, 2011, 05:20:24 pm
The one I owned RE model would start 2/3 kick's every time even after 6 months sitting .i think that twin ringed motor was tough as nails and went v good .the spares kit that came with the bike had just about every thing you needed for a couple seasons of club riding great thing.only let me down once stator died one day when riding it.
Title: Re: Honda CR125 r
Post by: Slakewell on March 06, 2011, 05:30:29 pm
These things were like hammers.
If it has good spark and doesn't start easy is the plug wet when you check?
Also might check the funky atec exhaust whosit on these things might be getting stuck and not allowing the motor to breath freely at first.
Title: Re: Honda CR125 r
Post by: evo550 on March 06, 2011, 06:37:10 pm
Ok I've officially put up the white flag.
I have just accquired a 1984 cr 125, BUT it is a absolute mother to start.
Thats not to say the bike dosnt run, it does and sounds fine when it is running.
But getting to that point is hurrendous.
I have done all the regular stuff.
1. Checked fuel flow.
2. Cleaned carb and checked settings.
3. Checked ignition timing. (With a dial gauge and cyl head off). Spark is strong
4. Checked reed block petals.
All is as per mister Honda says it should be.
Is there anyone out there with a idea ?
This bike is destined for the back of the shed.
Steve.
 :(

What condition is the top end in ??? Worn piston/rings=low compression=hard to start
Title: Re: Honda CR125 r
Post by: GMC on March 06, 2011, 06:47:23 pm
What condition is the top end in ??? Worn piston/rings=low compression=hard to start

I'll second that.
Title: Re: Honda CR125 r
Post by: jawa76 on March 14, 2011, 03:41:28 am
Thanks for the advice guys, Ive decided to pull the engine out a and do a full rebuild.
Title: Re: Honda CR125 r
Post by: DOK on March 14, 2011, 01:34:10 pm
Thats a bit hash as a starting point.
1st check compression with a gauge maybe pop down to the local bike shop or mechanics for this. a real sad engine will be below 90psi.
2nd moer likely to be blocked low speed jet. whith new fuels these get gummed up real easy. again try the local bike shop take just the carbie and ask for it to be cleaned and set up. (Float level).
3rd new fuel and plug.
Do the simple things first.
ps check compression with full throttle or carbie removed 4-5 hard kicks should give a true reading.
DOK
Title: Re: Honda CR125 r
Post by: VMX247 on March 14, 2011, 01:53:00 pm
Check with a timing light !!
Check for cleaning cloth/rag not jammed in some where !!
cheers A
Title: Re: Honda CR125 r
Post by: jawa76 on March 24, 2011, 09:38:59 pm
Thanks for your help guys, I went ahead and pulled it all apart, and done a rebuild.
Unfortunately found some serious problems we now have rectified.
Rode the bike at Heaven Bulladelah meeting, and all is now good. Some small chassis tidy ups but in general all smiles now. ;D