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Re: Cold rear

Posted: Fri Oct 08, 2010 10:34 pm
by samace
Cammo wrote:
samace wrote:The choke made no difference at all if any thing it did not help bike to start I am still waiting for my new pilot jet. Is it worth dismantlining choke side as I have not touched it yet.
That's typical symptoms of the enrichening (choke) circuit not working corectly. Pulling each choke plunger out and spraying with carb cleaner will probably not solve the issue, at least it hasn't in the past for me.


Finding a cheap ultrasonic bath that's big enough for each carb is a task, but it's on my wanted list as carbs with these issues are probably salvageable. Buying a known good set of used carbs might be cheaper in the short term.
I have taken all choke mechanisms out to find them furred up and green where they fit into the holes. Where they lead to these holes were blocked also. I got some thin wire cleared all holes that led to choke and then cleaned them with carb cleaner and blew them out with compressed air. I then ordered the carb springs and shims for needles from Rick Oliver. All float hieghts were correct and mixture screws have been set to 1 5/8 ( originally 2 1/4). The carbs are now on the bike and started up pertol poured out the overflow for a little as I think the bike was on its side and they were a bit stiff. I started the bike today and is the first It responed to choke and revved to approx 4k ( a good sign).I also noticed it fired on all 4 cylinders from start also ( never happened before). I let the bike warm up for a few minutes and the bike seems to rev fine. (b4 a bit slow and fluffy . I am in the process of recovering the seats and will be done tomorrow hopefully, will then take for a test ride but know its gonna be good !!! as it responds 200% better than before. Thanks for your help and advice !!



:rocks:

Re: Cold rear

Posted: Fri Oct 08, 2010 10:39 pm
by Cammo
Good result!

When you take it out for a spin let it get to full temp and give it a thrash to clear it out. She'll love you long time for it.

Re: Cold rear

Posted: Sat Oct 09, 2010 4:04 am
by Harvd
This is exactly what i wanted to read. Guess i better get those choke mechanisms apart...

Re: Cold rear

Posted: Sat Oct 09, 2010 10:59 am
by CMSMJ1
Cammo wrote:Good result!

When you take it out for a spin let it get to full temp and give it a thrash to clear it out. She'll love you long time for it.

Sucky fucky five dorrar?

Good work Cammo and Samace.. :peace:

Re: Cold rear

Posted: Sat Oct 09, 2010 9:51 pm
by Harvd
Hmm these damn carbs are spotless on the inside. Now that i think about it ive never actually unblocked any gunked up passages in all the times ive been in them... now im assuming that i could only unblock the 2 passages that you can see when the diaphram cover is taken off? or are there more choke related holes in there?

I almost wanted to see them all gunked up...

Re: Cold rear

Posted: Sun Oct 10, 2010 1:26 am
by Harvd
Did a bit more reading with the help of google, and finally realised that the 3rd brass jet thing in the float bowl (the 1 next to the main an pilot) is the starting and enrichment circuit thingy (i think). So carbs off again and with a bristle from a stiff wire brush unblocked the tiiiny wee holes in it. Finally for the 1st time since ive owned the bike i can use the choke to start the bike. And throttle response is much better too. Very glad i read this thread :grin:

However when warm and idling if i pull the the choke the bike dies however i can use the choke to start it. Is this normal?

Re: Cold rear

Posted: Sun Oct 10, 2010 5:40 pm
by samace
Harvd wrote:Did a bit more reading with the help of google, and finally realised that the 3rd brass jet thing in the float bowl (the 1 next to the main an pilot) is the starting and enrichment circuit thingy (i think). So carbs off again and with a bristle from a stiff wire brush unblocked the tiiiny wee holes in it. Finally for the 1st time since ive owned the bike i can use the choke to start the bike. And throttle response is much better too. Very glad i read this thread :grin:

However when warm and idling if i pull the the choke the bike dies however i can use the choke to start it. Is this normal?
I think you'll find that is normal mine does the same. I took mine for a good thrashing today with a shim 0.5 shim under the needle it is still very slightly hesitant @5.5k. So I took it out and it is worse. Will it do any good putting a 1 mm shim under the needle ? The only thing I noticed is that in 1st gear it pulls through but gets worse as it goes up the gears as you go through 5.5k ( unless you go through quickly, but still not perfect). I also have a NC30 which pulls very good all the way through (0.5 shim under needle and drilled slides). Is my best solution putting nc30 carbs on?

PS. If you have carbs off put Allen screws on the carb slide caps makes it easier to get off when playing with needles !!!


:rocks:

Re: Cold rear

Posted: Sun Oct 10, 2010 8:25 pm
by Harvd
Is that an additional 0.5mm shim to the factory one or is it just the one 0.5mm shim? No shim should be worse as its a lean spot around those revs and lowereing the needle further leans out the mixture i would try 1mm total (thats what im running) shims and if thats no good, back to standard...

Re: Cold rear

Posted: Sun Oct 10, 2010 9:26 pm
by samace
Yes that was 2 shims 1mm in total under needle will 1.5mm be any Good !!!
Its was ok with 1mm but have not had it runnung properly with standard 0.5mm thaought id try it and it was worse. 1mm was better. but will 1.5 be better again ?

Re: Cold rear

Posted: Mon Oct 11, 2010 12:27 am
by Cammo
samace wrote:Yes that was 2 shims 1mm in total under needle will 1.5mm be any Good !!!
Its was ok with 1mm but have not had it runnung properly with standard 0.5mm thaought id try it and it was worse. 1mm was better. but will 1.5 be better again ?
I don't think you should need to go to 1.5mm but you could always give it a try. It will be too rich on most bikes.

Are you using a standard air filter??