2001 CR125 jetting - continued

**morg_nz** · 2nd March 2010, 13:03

Finally found time to have a look at my carb - after playing with the air screw and having to get it out to about 5 turns to make it run better.

Anyways - according to city honda in PN, the factory settings for a 2001 cr125 are as follows:

Main Jet 360
Pilot 50
Needle 3rd from top
Needle 6beg20-69

what i found in my carb however was:
Main Jet 350
Pilot 32.5
Needle On top
Needle 6beg21-68

any ideas what this means? from the position of the clip on the needle, i'd say that the last owner was trying to go leaner - which would fit with my impression of the bike being rather rich (a lot of black crap on the exhaust and a badly fowled plug).

I understand that having the needle on the top clip is not idea, so I should prob get a leaner needle that I can run in the 3rd clip or so? But how do I find out what needles are leaner, and where could I get one? (I cant seem to find anyone in nz who sells jetting stuff on the net)

Any help would be much appreciated - Cheers Morgan

**Jinxycat** · 2nd March 2010, 14:07

you could either,
1. buy the jets and needle from honda.
2. buy a dynojet kit or jd jet kit, these both come with jets,needle and full fitting and set up gide.

try your needle 3rd clip from top and see, glad to see you found the factory set up

**Reckless** · 2nd March 2010, 15:21

Hey morgan
From the look of what you have written above your quite close to factory as long as the 32.5 figure is the size of the pilot.
You have similar settings except for a couple of clips leaner on the needle. I would be hesitant to go leaner than factory until you have checked the other things hereunder. The bike should go ok??

I'd be looking for another problem! ie, blocked vent hoses, broken or cracked carb boot, wrong float level, float needle valve not seating and leaking fuel, dirt some where, broken reads, leaking crankcase seals, Carboned up/jambed power valve, check and de-coke your pipe!

When was the top end done last?? Compression? And was the Power valve serviced?? Is it working properly?

Thoroughly clean every ventury in the carb, everything, set float levels, check float needle valve for seal, remove the vent hoses and clean, check as many of the things as you can (listed above) before you go buying leaner jets/needles than standard.

PS don't start new threads all the time, people offering fixes need to know the history or the advice you get may be false?
Previous thread http://www.kiwibiker.co.nz/forums/sh...-CR125-jetting

Thats my take???

Btw: Don't look for good power from a 125 way down low, but if you have a flat spot or a complete dead spot from zero throttle to say 1/4 or half its still the pilot circuit or something effecting it. IMHO!

Best advice I can give over the net??

EDIT: make sure the floats (or one of them) are not holed/cracked and filling with fuel?

OH shit forgot the first thing you should always try on a smoker LOL!! A fresh plug?

Thats my smoko well gone lol!! Back to designing additions!

**morg_nz** · 2nd March 2010, 16:31

Thanks for that reckless - will try another plug too.

MORE INTERESTINGLY THOUGH - I just put the carb back together (all i changed was the position of the clip on the needle - down to 3rd), and went to start the bike. it started first kick, but for some reason the clutch wouldnt disengage when i tried to ride it. any ideas what i've done, as it was working when i rode it into the shed the other day?

**Reckless** · 2nd March 2010, 17:11

Originally Posted by morg_nz

Thanks for that reckless - will try another plug too.

MORE INTERESTINGLY THOUGH - I just put the carb back together (all i changed was the position of the clip on the needle - down to 3rd), and went to start the bike. it started first kick, but for some reason the clutch wouldnt disengage when i tried to ride it. any ideas what i've done, as it was working when i rode it into the shed the other day?

If you have moved the C-clip from the top of the needle down to the 3rd clip position, what you have done is raise the needle and let more fuel in? If you thought it was rich before it should be worse now? What has actually happeded I reckon (as long as it rides ok) is you have cleaned or fixed something un-knowingly with your maintenance regime. Probably the float needle seat or a blocked vent?? Often happens!

Clutch is a completly different problem. How often do you change your gearbox oil? Some do it every ride on a 125 but every second or third should be ok for trial riding. 125's give their oil and clutch asrsholes! Oil your cable, check its pulling ok. If its ok your gonna have to strip the clutch out and check the plates, springs and spacers for wear, check the widths with a micrometer against factory. Then look for notches on the clutchbasket which catch on the plates. You can gently file these smooth making sure all the basket teeth are the same width at the end. ie don't file the shit out of one of the clutch fingers so plates don't drive off them all evenly! you will only renotch the widest one really fast!

OK thats it for one day! You owe me a beer! I have to do some freckin wrok now LOL!!!

**Jinxycat** · 2nd March 2010, 17:23

Originally Posted by morg_nz

Thanks for that reckless - will try another plug too.

MORE INTERESTINGLY THOUGH - I just put the carb back together (all i changed was the position of the clip on the needle - down to 3rd), and went to start the bike. it started first kick, but for some reason the clutch wouldnt disengage when i tried to ride it. any ideas what i've done, as it was working when i rode it into the shed the other day?

on the cr carb you can pull the throttle cable and the outer dosnt sit back into the carb top properly, it will if you grab it and push it in, just a cr thing to look out for as it wont run/start if this has happened

**morg_nz** · 3rd March 2010, 19:34

still having no luck with the clutch? any more ideas?

**Jinxycat** · 3rd March 2010, 20:00

does the basket fingers have notches, are the steals flat and not blued?

**morg_nz** · 4th March 2010, 05:54

I havent pulled the clutch out yet - thats tonights job. but what confuses me is taht it was working perfectly when i put it away, then i started playing with the carb and now it doesn't work - im thinking i knocked something but i cant figure what?

**Reckless** · 4th March 2010, 08:14

You could only have twisted or pinched the clutch cable making it inoperative when putting the bike back together.

Nothing you do to the carb can affect the clutch except for the above!

You best check the cable first as its sounding very much like you should be getting someone that knows bikes better to look at it for you?

But it could be coincidence and your clutch may a have failed just then?? We can't tell over the net?

**Jinxycat** · 4th March 2010, 09:23

Originally Posted by Reckless

You could only have twisted or pinched the clutch cable making it inoperative when putting the bike back together.

Nothing you do to the carb can affect the clutch except for the above!

You best check the cable first as its sounding very much like you should be getting someone that knows bikes better to look at it for you?

But it could be coincidence and your clutch may a have failed just then?? We can't tell over the net?

yup, i agree with reckless, if it was ok before you pulled the tank off (i assumed the clutch was poked along with the jetting......that will teach me to assume) it is probably cable routing.

**morg_nz** · 5th March 2010, 11:08

so i pulled the clutch apart last night - I think it was the springs that are the problem as I have an "old" cr125 clutch, and the springs in that are longer than the springs that i pulled out of my bike by about 1mm on average - which would account for why its not disengaging (i hope) so its a new set of springs - oh and the friction plates and steels looked in mint condition, no warpage or discolouration, nad the basket was sweet too. maybe the previous owner replaced the springs at the same time as the rest and they were just shit/the wrong ones?

anywhoms - after reading an ADB magazine i decided to lay the bike on its side to change the clutch (to save changing the oil at this stage). what is intersting though is that i've come back to the bike today, and all the gearbx oil is on the ground - it seems to have come out an overflow pipe. i didnt think there was an overflow from the bottom of he engine? or is there definately not one and i have a leak somewhere?

**B0000M** · 5th March 2010, 12:21

isnt there an breather/ overflow from the top of the gearbox on those? at the back end somewhere

longer springs shouldnt cause it to not disengage, unless its preventing you from pulling in the lever.

things that cause poor disengagement are usually a worn clutch basket - look for ridges down the sides of the 'fingers' remember the clutch plates need to be able to slide against these whilse having pressure pushing on them toward the fingers in order for them to disengage. another thing that causes poor clutch action is the wrong oil. - what kind of oil are you running? i know honda reccommends engine oil of some sort, but most people i know use a standard automatic trans fluid as gearbox oil and are yet to run into problems (about 16 years worth of use for me)

also, honda clutches never disengage that well anyway, eg its likely to stall when you first put it in gear for the day, and its unlikely youll be able to start the bike in gear with the clutch in.

**morg_nz** · 5th March 2010, 13:46

Yeah i thought it must be an overflow becuase of how freely it was coming out.

As for the springs, what i think has happened is that the ones that are in there are worn, and have been compressed (i.e. are shorter) and are not long enough to allow the clutch to release any more.

Originally Posted by B0000M

isnt there an breather/ overflow from the top of the gearbox on those? at the back end somewhere

longer springs shouldnt cause it to not disengage, unless its preventing you from pulling in the lever.

things that cause poor disengagement are usually a worn clutch basket - look for ridges down the sides of the 'fingers' remember the clutch plates need to be able to slide against these whilse having pressure pushing on them toward the fingers in order for them to disengage. another thing that causes poor clutch action is the wrong oil. - what kind of oil are you running? i know honda reccommends engine oil of some sort, but most people i know use a standard automatic trans fluid as gearbox oil and are yet to run into problems (about 16 years worth of use for me)

also, honda clutches never disengage that well anyway, eg its likely to stall when you first put it in gear for the day, and its unlikely youll be able to start the bike in gear with the clutch in.