Custom Fighters - Custom Streetfighter Motorcycle Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #1 ·
Dose any one have any info on how to time/setup the points on a cb 125 possibly xl 125 it dose spark just not at tdc what are the timing marks? cant find any info any where on this also there is no bolt in the end of the shaft for the cam that activates the points arm is this just a 10 mm bolt with a washer?

Any help greatly appreciated!!!!!!!!!
 

·
Is my bike ok?
Joined
·
15,255 Posts
I have zero experience with the 125, but I'm pretty familiar with the CB 750's. Its a good chance Honda set them up the same way. When I get in (to a real computer) I'll put up what the FSM has for those.

Do you have any pics of the points plate we can look at? We might be able to figure it out without ant literature. A lot of these setups are pretty common / reused between models.
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #3 ·
i dont sorry its not my bike trying to help out a friend get his first bike on the road.

I'm not sure I remember it but I think you set the flywheel to TDC and
line up the points back plate mark with the mark on the engine.
Then set the points gap.

i did find this but its for a cb 360


I will see if i can get pics of it for you!!!!!!
 

·
UnicycleMode
Joined
·
7,584 Posts
CB125 points and CB360 points should be the same when it comes to the design and adjustment. Should be able to line up the crank at TDC and set the timing plate without much problem.




I have some stuff to unload from my truck into the shop this morning so I'll check my '74 XL125 engine (same thing as the CB/CL 125's) and see if I can come up with a picture and an explanation for some better advice on how to get it adjusted into spec and working proper. ;)
 

·
UnicycleMode
Joined
·
7,584 Posts
Okay, took a shot of the timing marks for you and the complete assembly of the points as installed by Honda (never been removed or changed on this engine) so you can get your friends bike sorted. The ignition CAN BE SET 180 DEGREE'S OFF. Meaning BDC can be mistaken for TDC. ;)



The cam end does have a marker for TDC. Here is pics of mine properly timed. :)











When the T and F markers are lined up with the tab in the cover you are at TDC, it will be a little off from there at BDC. Pretty easy to note when it is at proper TDC.
 

·
Is my bike ok?
Joined
·
15,255 Posts
The "T" mark is for finding TDC. The "F" mark is the one to adjust your points to(where it fires). Verify that you are actually at TDC (not 180* out) at the "T" mark. Then turn in the direction of operation to the "F" mark. Adjust your points there. If you adjust with the test light procedure you'll be pretty much dead on the money.
-Set engine to "F" mark.
-Connect your test light so it is reading thru the points to ground. It will light up when the points are closed.
-Rotate points plate until the test light juuuust goes out.
-Tighten the points plate there and you're done.
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #7 ·
thanks for all your help guys i think i get the idea now set the crank to f for fiering point and t for valve timing so set crank to t then set the cam to open them at the right time then set the gap between the points (dose any one know what the gap should be?) sounds simple enough should be over ther tuesday so ill let you know how i get on!!!!!!!!!
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #9 ·
ha ha yeah thanks for reminding me rob!!!!!!!!
 

·
UnicycleMode
Joined
·
7,584 Posts
Did a little digging and came up with the points gap, seems to be the standard of Honda, Shiny posting one from the big CB and this little one running the identical specs leads me to believe that there isn't much out there that can't be tackled on a Honda motorcycle once you have a basic knowledge of them:

CB125 breaker points gap

0.3-0.4mm/0.012-0.016"
 

·
Premium Member
Joined
·
50,679 Posts
Did a little digging and came up with the points gap, seems to be the standard of Honda, Shiny posting one from the big CB and this little one running the identical specs leads me to believe that there isn't much out there that can't be tackled on a Honda motorcycle once you have a basic knowledge of them:
CB125 breaker points gap

0.3-0.4mm/0.012-0.016"
so i am OK with gettin one ?
 

·
old fart
Joined
·
3,825 Posts
Did a little digging and came up with the points gap, seems to be the standard of Honda, Shiny posting one from the big CB and this little one running the identical specs leads me to believe that there isn't much out there that can't be tackled on a Honda motorcycle once you have a basic knowledge of them:
WORD;););););)
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #15 ·
thanks for that guys.
Yeah it sounds like they all have the same points gap cos the cb360 in the vid is the same too.
As for hondas all being very simmilar if not the same it is one thing i like about them makes it so easy to work on them and a lot of part are interchangable thats why my bike is a mix of cbr and hornet...
 

·
UnicycleMode
Joined
·
7,584 Posts
I like the Suzuki LEGO's myself. :thumbsup:






The interchangeability (<---fucking awesome word!) of most manufacturers parts with one another is amazing to say the least. I have a huge parts bin I dig through pretty regularly and once I get it more organized I will be in heaven picking parts and matching them up for builds. It's already to a point I have GasGas and Brembo parts on my DRZ400S. :D
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #17 ·
Good news i got it going today and all youre help was spot on guys thanks

So heres how it went I set the crank to tdc set the points plate to the mark on the casing then set the points gap kicked it over nothing wtf. So went through it all again about four times even made shure I dident have bdc not tdc. No i had it all right but there was one thing that was bugging me as you look at the points there is a cam that moves the points arm and a bolt in the end. But when i first looked at it there was no bolt there and the cam was able to move free from the shaft untill i put a bolt in to hold it. There was a line on it I thought was a timing mark so i tried lining it up with different marks on the plate but none made sense. So i decided to take the ponts plate of compleatly to see what was going on behind it and I found a mechanism a bit like a central fugal clutch i can only guess as it opens and moves the firing point but not sure. Any way I took that of the shaft and found that it should be held to the shaft with a pin but no pin. A bit of a look about and it was found down in the casing how it got there fuck knows. The engine has just come back from being rebuilt by a bike mechanic so all i can think is that by not putting the bolt in the end of the shaft the mechanism has move and the pin fell out and put the timming out.
A quick reasemble of every thing one good kick and it came to life set the tick over so it wasent reving it head of and it sat ticking over fine give a fist full and it died a bit of a think prehaps the point are out slightly. So started it up losend the points plate slightly and move it round till the bike reved smoothly tightend every thing back down.
JOB DONE!!:letsride:
Then for the fuck of it we started taking of all the crap indiys gone head light gone clocks gone wires rerouted side panles gone looks a lot cleaner then the plans started single spot on the front small round speedo set of drag bars cut the sub frame cut short cut seat down to a single cut the huge exuast down so its under the engine and longer shocks in the back to raise it slightly then ride the fuck out of it!:rock:

And as payment for sorting it out the square head light got donated to a good home on the front of my cbr!!!

And again many thanks to you guys for all the info couldent have don it with out it THANKS:rock::rock:
 

·
Registered
Joined
·
1,350 Posts
Discussion Starter · #19 ·
When we took it out to the car park to test it it pulled nice and strong all the way through the revs i was supprised how hard it pulled for a 125!!!!!!!!!
 
1 - 19 of 19 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top