Has anyone had that problem. I had the spark plugs changed by a competent motorcycle mechanic and I notice on start up that my throttle is sluggish at first, and sometimes when riding. In neutral at start up, I rev it about and it doesn't catch, then after a few times it does, say after a minute or warm up time. Before I never had to warm up the bike to get instant response. Has anyone had this problem, or know what to do to remedy the situation. The mechanic spent like 2 hours changing the damn things, so I don't want to have to go back and have him redue the gap or to check it out. Thanks...

 

So many views but no responses. Now the problem is worse. I'm getting hesitation at start up and now when I'm riding. Usually from 1st gear. Its annoying because I give her gas, than it hesitates for the first 2000rpms or so, than it just kicks *** with instant accelaration out of nowhere. It kind of makes driving in first gear a challenge. What to do, again it all came about after the spark plugs were all changed by the mechanic. Wish I never did it....Any suggestions, anyone. Not sure if I want to take it back to the mechanic.

 

take it back and get him to fix it i think its obvious cos he must know what he did to it

 

did he
1. use the right type of plugs
2. tighten the plugs to spec so you dont lose compression
3. put the correct plug wire on the correct plug
4. remember to plug in the MAP sensor on the bottom of the airbox

sluggish operation is a lot of times caused by too much air

i bet that he forgot to plug in a vacuum hose somewhere

 

I'm not sure if he did all those things, but I hope he did all of that. Now that you mention it, he did say that there was this one vacuum hose that was just hanging there, and it wasn't plugged in anywhere. He didn't know much about it. But he said that he left it the same way that I originally brought it to him. I'm wondering now... I guess if you want a job done right these days, you are better off doing it yourself. I might go to another mechanic and just pay someone else to check it out.

 

The best way to fix your bike is to do it yourself. Find a manual for your bike and try to trace yourself where that vacuum hose should fit. Or if you post up a picture, someone out here might be able to help.

 

how can he be competent if he doesnt even know where the vacuum lines go

if it is about 1/4 inch then it needs to be plugged into something
it is probably the map sensor

there are two 1/2 inchish vent tubes coming out of the tank that go down by the shift linkage
they dont plug into anything

 

Yeah so I'm thinking it was the vent tube that he located and didn't know what it was doing there. It seems that the problem has gone away on its own. The throttle is instant now. Thanks guys.