Bike wont stop throttling.

Aug 14, 2016
58
4
8
Texas
So yesterday I took my,bike to high speeds. Motor sounded so smooth. But as I slowed down, I noticed it would not stop completely. I grabbed the clutch but my engine revved up high and scared the **** out of me. I've adjusted the throttle line at the carb and the grip but the problem persists. What do I do?
 

Tony01

Well-Known Member
Nov 28, 2012
1,384
814
113
sf bay area
Sounds like an intake air leak is causing the mixture to lean out. Check your gaskets and flanges for flatness!
 
Aug 14, 2016
58
4
8
Texas
Loll I showed my grandpa the thing that sits between my exhaust and engine and he told,me it long needed cleaning. So I stuck it,in gas for right now. Will I need to buy another? Also oil leaks out at that location instead of at the bottom of my exhaust.
 

Tony01

Well-Known Member
Nov 28, 2012
1,384
814
113
sf bay area
Well now you'll have to put new exhaust gaskets too. But the problem isn't in cleaning, it's in your intake.
 
Aug 14, 2016
58
4
8
Texas
I don't know what that is. This is my first build. I assume you mean the connection between my engine and carb. The screws were loose on the connection, not the carb itself,but the metal from the engine into the carb. I tightened it.
 

Slogger

Member
Sep 8, 2014
545
4
18
nohio
I don't know what that is. This is my first build. I assume you mean the connection between my engine and carb. The screws were loose on the connection, not the carb itself,but the metal from the engine into the carb. I tightened it.
You can take that thing (intake manifold) off, put some emery cloth or even sandpaper on a flat glass table, and sort of polish the mating surface of the flange down flat. The idea is to get an airtight seal at the flange where it bolts on to the engine. The engine surface is usually ok.
I put some gasket seal (a thin coat of permatex high heat copper stuff) on both sides of the gasket to make sure it doesn't leak any air. A little goes a long way, don't overdo it and have a gob of it in the air passageway.
The engine needs to suck its air through the air filter/carb throat, you don't want it to get in from any other place.
Another good thing to do is to make sure the carb is pressed onto the manifold as far as it will go until those notches in the end of the manifold are inside the carb. Some leak there, too.
Keep a little force on it as you tighten the clamp screw.
good luck! ;)
 
Last edited:

Tyler6357

Well-Known Member
Mar 15, 2012
1,119
163
63
Santa Barbara, CA
If the intake was loose then you probably found your problem, just make sure it's tight and test. It sure sounds like your had an air leak.