Sounds great in neutral, bogs and stalls when accelerating in gear

[kdsd731]

A neighbor of mine brought me his old banshee to try and get it running. It sat for 5 years outside. He had a shop a long time ago install toomey T5's, a k&n filter no air box and rejet it. he said it ran fine a long time ago. I cleaned the carbs very thoroughly. Every jet is spotless, every passage passes carb cleaner through it and the needle is spotless and is on the #3 clip position. I replaced the fuel with 91 @ 40:1 with yamalube 2r. The K&N is clean and oiled. The compression is 130 psi in both cylinders. the reeds are oem and brand new. I didn't pay attention to the jet sizes since he said it was rejetted by a factory yamaha dealer and it ran great before parked.

It starts easily, idles smooth and has a great throttle repsonse in nuetral. Once in gear and trying to accelerate it bogs out. I can get it to go if I really play with the throttle. Any suggestions?

[n2otoofast4u]

stock carbs? Id richen it up on the bottom end and see what it does.

[ClayAiken]

Doesnt the parking break do that when it messes up? Could be wrong, Im almost positive. Does it have it? if it does id remove it.

Edited February 27, 2012 by Hyper

[kdsd731]

The parking brake doesn't have a switch on his.

 

And you think the jetting needs to be changed even though it ran great before he parked it with these jets?

[Sandking]

Did you check the stator or maybe switch with a known good one. If everything mechanical is good then it maybe electircal.

[ClayAiken]

The parking brake doesn't have a switch on his.

 

And you think the jetting needs to be changed even though it ran great before he parked it with these jets?

No i wouldnt say it would be jets normally with wrong jets it wont idle and doesnt rev right. I agree with SandKing my guess would be electrical i would test the stator trace all of your wires to the harness it sounds electrical to me. I could be wrong where it was outside something may of eaten a wire. Thats my best guess its going to be something stupid.

[toytech]

I had one last summer with the same symptoms, everthing checked out ok, so we started swapping electrical parts and the coil fixed it.

[guns4children]

My serval build was the same way. I trimmed a bit off the plug wires and reinstalled the caps. Thing run like a champ after!

[kdsd731]

I will check the ignition system. What about T.O.R.S.? How can I completely disconnect it? When I first started it, it wouldn't take any throttle in neutral at all with out stalling. I disconnected the throttle sensor and jumped the harness side of the connector to bypass the switch. Then it revved in nuetral great.

[kdsd731]

I checked the ignition system and every thing seems good as a static test. I trimmed the coil leads but no change. The stator is good doing a static test. the ignition coil is good. I pulled off the carb to check the jets since that is the only thing I didn't pay attention to. The pilot is a 25 and the main is a 280. The clip is on the #3 position on a stock needle. Fuel level is just below the float bowl gasket. The spark plugs are a perfect tan color. And as reminder, he has a stock engine, T5's and a single K&N that splits to the two carbs and has no air box. What do you think about jetting? We're in So Cal at around 1,500ft and about 55f right now. It is only ridden at Glamis too.

Edited February 28, 2012 by kdsd731

[guns4children]

I would say he needs a 27.5 pilot.

[Sandking]

What year bike is this and does it have the parking brake sensor? If it does disconnect it and try that. You should also disconnect the tors they cause problems also.

[kdsd731]

It's an 87 and has no parking brake sensor. It has a small cap where the sensor would be. Also, i disconected the tors black box. Is that you do to bypass tors?

[bigboybanshee]

It sounds like a lean condition to me. Try richening the needle.