1977 cr125 carb size Part# 16 13 442-01 ?

Hello,
I have done some research, but not coming up with much. From what see this far is that the carb was a Bing84? Now there are a couple of different types of Bing 84's out there I know. I need help finding exactly the kind I need. If all else fails, is there another carb that will worth with little to no jetting.

Any help is greatly appreciated.

Thanks,
Chris B

Chris.

Chris,

Husky Part # 161344201 = Bing carb # 84/32/112

Marty

Marty,
Thanks for getting me this info. I was not able to find a brand new one so i purchased a mikuni vm 34- 389. setups for this carb on this bike i am unable to find on this sight. i know all bikes are different.

this is what i Purchased....

SPECIFICATIONS:
Spigot OD: 40 mm
Bell OD: 58 mm
Main Jet: 330
Pilot Jet: 30
Air Jet: 0.5
Needle Jet: 159 Q-2
Jet Needle: 6DH2
Throttle Slide: 2.5
Choke Type: Cable.................< I changed to lever choke.

I think that the main jet is fine. I am concerned about the pilot jet( think it should be about a 35), the needle and air jet. I think the Air jet should be about a 1.7.

PLEASE HELP WITH THIS IF YOU CAN. Get me to a starting point. Currently it is installed and running. It bogs from 0% to 70% throttle. when riding it takes a few for it rev due to lack of fuel? When it gits the powerband of the rpm it ******* screams and the clutches slip i think. It Hits Hard!! LOL

Chris,
I don't think you jetting is to far off. Is this a known good running motor before the carb swap? Do you have fresh as in new gas/oil mix?

Try this for your Mikuni 34
main 310 to 280
needle jet 159-p-8
pilot 40
jet needle 6F15
slide 2.5

Much appreciated buddy!

Thanks,
Chris B

sorry is in french !
carb MIKUNI 34 mm
125 WR
possible translate in englisch

for bing no problem parts
in europe !

This info is really useful, thanks for reading this thread.


Thanks buddy!

Did you mean 310 to 380 on the main Jet? I got all the parts in and went from 330 to 310 and i think it leaned it out. I will install 330 back in it and test soon.

Thanks again!! much appreciated!

Chris B- Careful on copying "bits and pieces" of jetting specs... the needle jet and more importantly the needle taper(s) can make a huge difference. And the pilot jet provides some fuel up to full throttle too.

The 6DH2 needle looks to be "thicker" (leaner) near the top of the needle than either the 6DH4 or 6F15 which will make the 6DH2 needle leaner at part throttle.

Needle taper charts are available online.... Sudco catalog has them. The charts give the diameter of the needle at specified points so you can fine tune the fuel delivery at different throttle settings. So say if you are too lean at half throttle but fine at 3/4 throttle you pick a needle that is smaller in diameter at about the half throttle point on the needle and about the same diameter at the 3/4 point on the needle.

A while back I found a list of 6 series needles listed "in general" from lean to rich:

(use at your own risk... I don't vouch for the validity of the info below)
LEAN
6DH2
6DH3
6DH4
6DH7
6DH8
6DP1
6DP4
6DP17
6F4
6F5
6F8
6F9
6F16
6FJ6
6L1
6N1
RICH

View: https://youtu.be/E9DXeFmtqNg

Chris
Just saw your thread. I just finished upgrading two 1979 125's. The modifications included going from the stock 32mm Bing to 34mm Mikuni carburetors. I also added an expansion chamber and did some mild port work following guidance from a Husqvarna service bulletin and a Pro Circuit article from back in the day. My final jetting is as follows;
Mikuni 34mm
Main jet 250
Needle Jet 159 Q8
Needle 6FJ6
Pilot 55
Standard Mikuni slide cutout
My altitude is sea level
Hope this helps. Regards, Sean

Wow!! Those bikes look really nice! I would try that but i do not have a the service bulletin to go by. I have heard of this article though..Where did you get the carb boot from. I cannot find one that will fit.

Chris
Good question on the carb boot. First, the 34 is a tight squeeze and the carb ends up being tilted at about 10 degrees ccw because the bowl doesn't quite clear the left side case by the kick starter. The boot I used is a husky 250/390 boot that fits the 36-38mm carb. I had thin rings machined to sleeve my carb inlets. I cut the inlet snout off an old 36mm mikuni to make them from, that way I only needed to machine the ID for a tight slip fit. I mounted the sleeves using loctite bearing mount stuff. The front airbox mount tab on the frame has to be slotted down a bit so you can rotate the airbox cow so it lines up with the new carb inlet. Like I said, tight fit. Works good though. Regards, Sean

Here are a couple of pics to show you what I described ....

One other comment; As part of my rebuild project I changed the pipe. The 34 mm carburetor and pipe together help this engine breathe properly and that made a huge difference in power output

Went to the up and over to other side like they did starting in 83 125. what pipe did you use as a start? 79-80 RM 125 was a good start for one I did.

Joe. You are right on the money. I bought a couple of RM pipes off of eBay, 79-80 vintage. Learned that was what the ProCircuit guys did back in the day... A little tight between the fuel petcock and the throttle cable but worked good otherwise. Also, be sure to check front fender clearance during fit up.

hello have done the same with my 125 from 1982.
rm pipe and it was fine
http://www.cafehusky.com/threads/125-wr-1980-to-82.78773/