Question about getting the rpm's higher?

32oday · #1 (**permalink**) 04-10-2009, 11:14 PM

I have a new motor and it runs great. The only thing I did was to shorten the chain to get rid of tension pully. Personally I think it is a bad design. Anyway my problem is that I choke this thing to get going and then slowly moving the choke down as it gets about half way it seems to run good but not great. As soon as I try to completely remove the choke it cuts out. It is the same thing over & over. Any Suggestions???????

goat herder · #2 (**permalink**) 04-10-2009, 11:37 PM

Try moving the clip on the needle valve, second from the top is where I think I have mine. Its the slide assembly in the top of the carb where the throttle cable attaches. Maybe that will help might need more info tho. Will it Idle at all Is the idle screw adjusted properly that would probly do that. Check first by turning it in.

**Bikeguy Joe** · #3 (**permalink**) 04-11-2009, 09:30 AM

I'd check for air leaks too.

Check the manifold to cylinder gasket and carb to manifold joints.

While you have it apart, use some silicone sealer on the gasket (both sides). Just a thin film.

32oday · #4 (**permalink**) 04-11-2009, 10:06 AM

In the break in period do you need to run the choke just half way or should you be able to take the choke completly off? Wnen I am running this thing 1/2 way choked as soon as I take thge choke off it cuts off.

Sidthekidd11 · #5 (**permalink**) 04-11-2009, 11:05 AM

this is exactly what happened to me. the problem for me was that the main jet was sitting in the middle of the float so if i were you i would take the bowl off and make sure your jet is attached.

**Norman** · #6 (**permalink**) 04-11-2009, 05:29 PM

You should be able to run with the choke completely off.
The choke lever down is off choke
When the lever is pulled up the choke is on.
If the choke lever is down and the engine dies then you will need to take a closer look at the carb.
Like the above posts says, check the main jet and the tube that the main jet is screwed into. you can check the operation of the throttle slide by taking off the air cleaner and you can see the way the choke works with the air cleaner off and working the lever you will see a metal plate go over the opening to the carb that is the choke plate.
If you want you can go to the classic posts I show how to work on the carb and take it apart.
Norman

32oday · #7 (**permalink**) 04-12-2009, 12:07 AM

Thanks for the help Guys.

NEAT TIMES · #8 (**permalink**) 04-12-2009, 12:37 AM

Reading This Thread May Have Just Solved My Problem. My New Diy Cvt Belt Drive Was Sitting Warning Up ( Running Perfect) And Just Stopped Like Someone Shut It Off. We Changed To Two Different Coils And It Would Not Start. It Fired A Couple Times When Choked But Never Started. Yesterday It Was Flooding. We Cleaned The Float Needle And Seat And It Ran Good. Now I Wonder If The Clip Came Off And The Needle Dropped Into The Jet!! I`ll Be Living Large Tomorrow If Thats All It Needs!! Ha Ha I THINK I PREFER THE DIAPHRAM CARBS, IN 30 YRS I HAVE HAD VERY LITTLE TROUBLE WITH CHAINSAW CARBY`S AND THE HAVE A FUEL PUMP BUILT IN. Ron

Venice Motor Bikes · #9 (**permalink**) 04-12-2009, 01:18 PM

Quote:

Originally Posted by 32oday

I have a new motor and it runs great. The only thing I did was to shorten the chain to get rid of tension pully. Personally I think it is a bad design. Anyway my problem is that I choke this thing to get going and then slowly moving the choke down as it gets about half way it seems to run good but not great. As soon as I try to completely remove the choke it cuts out. It is the same thing over & over. Any Suggestions???????

Two of the bikes that I built had that problem. (They only ran with the choke 1/2 on)
I took the carbs apart & found no obvious problems, or air leaks...
To fix this problem, I carefully drilled the jets on them and they both ran perfect after that!
If you feel you want to try this, Let me know & I will tell you how to drill the jet. (it's very easy)