No Power after 4k rpm on CB360

[ryzeabve]

I just finished switching out a rebuilt carb and new wiring harness on my cb360.. All the issues that were present prior to the swap are gone and I actually feel I can ride it without worry.. The only issue is there is really no power after 4k rpm?? I know its not suppose to be a rocket but there really is absolutely no power after 4k.. Any advice on where to start looking would be appreciated.. thank you..

 

[crazypj]

You have pods and modified exhaust.
Jetting is way off.
Other than that, it's normal so I'm nt getting involved

PJ

 

[djelliott]

Make sure your points are properly set.

 

[Big R]

+1 to both these guys. Have you adjusted the clutch cable at all? If it's not set right it can begin to slip at higher rpm. Also, make sure that all electrical connections are clean and have good grounds (especially with old coils).

 

[ryzeabve]

Its all stock, filter and exhaust.. Im gonna check out the pts and timing this afternoon.. I don't think it is the clutch slipping as I believe that the rpms would keep rising just wilth out any power going to the wheel.. Thanks for the advice..

 

[crazypj]

If it's all stock, check main jets haven't fallen out of emulsion tubes.

PJ

 

[Big R]

PJ, if the mains fell out, wouldn't it struggle to even idle?

Maybe there's an intake / exhaust leak that is messing with the mixture?

 

[ryzeabve]

checked the pts and timing and they were a bit off but not by much.. it did tighten things up a bit and it seems to have picked up a bit of power however it still feels slower than before the swap..

last year i had picked up a spare set of carbs off ebay for dirt cheap, at the time for the diaphragms as it was cheaper than buying those separately.. after having idle issues and one cylinder cutting out randomly i decided to thoroughly examine the spare carbs and they were in great shape internally.. i cleaned em up a bit and swapped em and it took care of the issues however, as i said, it seems that i had more power before.. maybe i just need to do a proper cleaning of all the passages.. I hadnt done so before cuz i looked at the jets and the visable surfaces and it was all clean..

what do you guys think about boiling them? i've heard some good things about that method but am not sure if its better than the old school carb cleaner, weld tip cleaners and some compressed air..

 

[Big R]

It's def possible to boil them. Somewhere on here (maybe the $50 mod thread) is a little guide to doing it. It was a mix of vinegar, lemon juice, and water I believe

 

[crazypj]

PJ, if the mains fell out, wouldn't it struggle to even idle?

Maybe there's an intake / exhaust leak that is messing with the mixture?

Nope, it's a 3 jet carb.
If secondary mains fall out, the pilot system still works until it transitions, at ...................4,500 rpm when slide starts to open.
It will run a little rich, but not enough to stop it.
It's why I initially thought it had modified exhaust and pods

PJ

 

[ryzeabve]

Alright I am happy to say that my issue has been resolved! I pulled the carbs today and went through em.. I'm not sure what solved my problem as I did a few things just to make sure that I wouldn't have to pull them again.. One of the diaphragm slides seemed a bit stretched and flimsier than my others so I replaced it with a decent one, not perfect but decent.. Also, I took out all the jets and reset them in to make sure nothing was loose.. Lastly I swapped my floats from my other set of carbs that I had properly set last season.. As nothing drastic was done, just minor possibilities, I really was not feeling confident that I solved anything however all that changed when I pulled away down the street!

Glad to say that I am officially done, at least for now, with all mechanical issues.. Now to start converting it to a cafe : ))