Ok i got gas leaking from my air filter also my throttle is kind of sticky when i give it gas and then back it off it takes time for the throttle to back off my motor anyone know how to fix any of my problems
leaking
- Thread starter smileymale
- Start date
the air filter, due to no reed valve in the engine, will leak some, it is routine to have to clean it periodically. be sure to shut off your petcock valve when you stop anywhere, even for a few minutes. Your throttle cable sounds like it needs a good lube, and/or strengthen your spring in your throttle body. ie. stretch it a bit( not too much though). You can lube your throttle cable with some 3-in-1 or some similar oil, I use honing oil, for sharpening stones. Someone will suggest a better alternative, like a brand name cable lube. I just happen to be the first one along. so wait for an expert to confirm/dispute! heh heh.
gl man.
gl man.
well just finished cleaning my air filter see what it does 2mrrow and the cable well i oil that 2mrrow also thxs 4 the advice
I fast idle, or slow to return to idle can also be symptoms of an air leak in the induction (intake) side. Make sure the carburetor is sealed to the intake manifold and the manifold gasket is sealed to the cylinder well. The kit supplied gaskets can leave something to be desired so make sure you have a good seal at the cylinder to manifold connection.
If you remove the air cleaner and look down the throat of the carburetor you'll be able to watch the carb slide (barrel) action as you twist the throttle. If it moves smoothly and returns to the idle position when the twist grip is released, look for the common air leak problem.
Tom
If you remove the air cleaner and look down the throat of the carburetor you'll be able to watch the carb slide (barrel) action as you twist the throttle. If it moves smoothly and returns to the idle position when the twist grip is released, look for the common air leak problem.
Tom
I had a similar prob, and it turned out that my throttle was sitting a little crooked on the handbars and was causing it to bind and slowly release. Make sure that the hole you drilled to "mount" them to the bars isn't to close to any bends and that the throttle spins freely....
I have built 20 motorized bicycles in the past year and have met several people in my area that have built their own.I have seen several weaknesses in these kits and try to address issues that have come up with past builds.What I do when I am working on the throttle assy is all of the above and here is my "methods".
When I unpack my throttle cable I wrap with tape on the handle end of the cable housing where the housing meets the adjuster to seal the housing and adjuster.
Then I squirt using the small straw/ tube several blasts of P-B-Blaster or w-d-40 into the bent guide tube and work the cable back and forth untill I get penitrating oil coming out of the other end.
Then I address the throttle housing and throttle handle.The throttle fits so sloppy in the housing I have found that if you twist the throttle the wrong way you can by-pass the throttle stop"not good" so what I do is drill the housing and insert a tension pin so the throttle stop hits the pin and cannot be twisted the wrong way by mistake.Then I cut off that little molded nub that is supposed to keep your throttle in place "yeah right"on the handlebars and drill a hole off-set enough to thread a m-5 button head cap screw down thru the housing.
Next thing I do is with a razor knife I trim all the molding flash from the inside of the housing,I also make sure where the throttle handle was molded is smooth,where the handle meets the housing.Then I "paint" anti-seize on all the wear areas.Including where the cable inserts into the handle and where the cable and cable end rides.Then I assemble the throttle assy together and measure from the inside of the handle to the center of the hole I drilled thru the housing.
With a magic marker I mark all around the area to be drilled on the handle bar.Then I slide the throttle assy onto the handle bar all the way and then back it off about 1/8" and tighten it down.
Then with the same size drill I used to drill the housing I drilled into the housing the handle bar Just enough to mark my location then I loosen the assy and slide it off.
Then I drill my hole in the handlebars and deburr the hole.Now I grease the handlebar with white litheum grease. Now I install the throttle cable and slide on the assy.I use the drill bit to locate the assy and tighten it down.
Then I remove the drill bit and tap the hole.Make sure your throttle cable housing isn't being kinked or bent and runs as smoothly as possible to the carb.
I port match the motors on all the bikes I build.
This makes them run stronger and Idle better.I carefully remove the intake manifold and with a razor blade I remove the gasket and mark the gasket with a sharpie marker the top on the motor side"for reference". If you look on the motor side of the gasket you will see the shape of the intake port. Very carefully with a razor blade trace along the edges of that shape.Don't try cutting through the first time trace it with the razor several times untill it's cut through.
Then I take a magic marker and color the flange of the intake manifold.Next I bolt the gasket to the manifold making sure that my reference mark is in the right location and I scribe around the inside of the gasket and remove the gasket from the manifold.
With my die-grinder I grind a nice gradual transision to my scribe lines.Also I look inside the manifold expecially if I have a kit that has one of those high quality cut/bent/welded manifolds.
I've removed welding flash from several manifolds that if it ever broke loose from vibrations it would of destroyed the motor!
While I have the manifold in hand I de-burr the carb end of the manifold and make sure it's cut square.I also die-grind the weld on the manifold,where my washers sit, making sure they will sit flat.
Then I rough up the carb end with 100 grit sand paper to help it seal.I also put a very small amount of rtv sealant in the 4 slots of the carb just enough to fill the slots,wipeing out any excess with my finger.
Then I install the gasket using a very light coat of sealant. Next I install the manifold and squirt a small amount of rtv sealant around the studs and install my flat washers and locks and nuts.
When I install the carb I make sure the carb is bottomed out on the manifold and that it is lined up vertically with the motor before tightening.
Then I put a small piece of shrink-tubing on the carb end of the cable housing and shrink that on and install the cap and slide into the carb.
After I start the motor and have had it running for a while and I'm satisfied with my adjustments I use a suringe with "green"loc-tite and squirt the top adjuster on the carb cap adjustment and the idle screw and let it set till the lock-tite is dry.
I'd do pics but I haven't figured that out yet!Hope I've helped! Kip.
When I unpack my throttle cable I wrap with tape on the handle end of the cable housing where the housing meets the adjuster to seal the housing and adjuster.
Then I squirt using the small straw/ tube several blasts of P-B-Blaster or w-d-40 into the bent guide tube and work the cable back and forth untill I get penitrating oil coming out of the other end.
Then I address the throttle housing and throttle handle.The throttle fits so sloppy in the housing I have found that if you twist the throttle the wrong way you can by-pass the throttle stop"not good" so what I do is drill the housing and insert a tension pin so the throttle stop hits the pin and cannot be twisted the wrong way by mistake.Then I cut off that little molded nub that is supposed to keep your throttle in place "yeah right"on the handlebars and drill a hole off-set enough to thread a m-5 button head cap screw down thru the housing.
Next thing I do is with a razor knife I trim all the molding flash from the inside of the housing,I also make sure where the throttle handle was molded is smooth,where the handle meets the housing.Then I "paint" anti-seize on all the wear areas.Including where the cable inserts into the handle and where the cable and cable end rides.Then I assemble the throttle assy together and measure from the inside of the handle to the center of the hole I drilled thru the housing.
With a magic marker I mark all around the area to be drilled on the handle bar.Then I slide the throttle assy onto the handle bar all the way and then back it off about 1/8" and tighten it down.
Then with the same size drill I used to drill the housing I drilled into the housing the handle bar Just enough to mark my location then I loosen the assy and slide it off.
Then I drill my hole in the handlebars and deburr the hole.Now I grease the handlebar with white litheum grease. Now I install the throttle cable and slide on the assy.I use the drill bit to locate the assy and tighten it down.
Then I remove the drill bit and tap the hole.Make sure your throttle cable housing isn't being kinked or bent and runs as smoothly as possible to the carb.
I port match the motors on all the bikes I build.
This makes them run stronger and Idle better.I carefully remove the intake manifold and with a razor blade I remove the gasket and mark the gasket with a sharpie marker the top on the motor side"for reference". If you look on the motor side of the gasket you will see the shape of the intake port. Very carefully with a razor blade trace along the edges of that shape.Don't try cutting through the first time trace it with the razor several times untill it's cut through.
Then I take a magic marker and color the flange of the intake manifold.Next I bolt the gasket to the manifold making sure that my reference mark is in the right location and I scribe around the inside of the gasket and remove the gasket from the manifold.
With my die-grinder I grind a nice gradual transision to my scribe lines.Also I look inside the manifold expecially if I have a kit that has one of those high quality cut/bent/welded manifolds.
I've removed welding flash from several manifolds that if it ever broke loose from vibrations it would of destroyed the motor!
While I have the manifold in hand I de-burr the carb end of the manifold and make sure it's cut square.I also die-grind the weld on the manifold,where my washers sit, making sure they will sit flat.
Then I rough up the carb end with 100 grit sand paper to help it seal.I also put a very small amount of rtv sealant in the 4 slots of the carb just enough to fill the slots,wipeing out any excess with my finger.
Then I install the gasket using a very light coat of sealant. Next I install the manifold and squirt a small amount of rtv sealant around the studs and install my flat washers and locks and nuts.
When I install the carb I make sure the carb is bottomed out on the manifold and that it is lined up vertically with the motor before tightening.
Then I put a small piece of shrink-tubing on the carb end of the cable housing and shrink that on and install the cap and slide into the carb.
After I start the motor and have had it running for a while and I'm satisfied with my adjustments I use a suringe with "green"loc-tite and squirt the top adjuster on the carb cap adjustment and the idle screw and let it set till the lock-tite is dry.
I'd do pics but I haven't figured that out yet!Hope I've helped! Kip.
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so to paraphrase -'Make sure there are no air leaks too'
It's a good wall of text if you can get through it, good tips kipharley.
It's a good wall of text if you can get through it, good tips kipharley.
Sorry for the long post! I just wanted to explain step by step how I address my throttle assy from handle bars to engine and try to make it as dependable as possibile.I just got carried away! Kip.
Thanks for the advice,I wasn't paying much attention in writing class! I was dreaming about my next build!Kip.
