Lurching in high RPM

[Clats97]

I have a GT5 pro racing, new build, stock. As I get above 25kmh, it starts lurching rhythmically. The jetting should be fine so I don't know what the problem is. Any ideas?

 

[inspectorcritic]

I just got one too.
I went back to a NT carb on cold take off it lurches too or jerks so f***ing bad it bends the bolts on my mag drive gear guess I going to put back on my pro carb got a crooked goose neck manifold.
I found out ran like s**t it made my CDI retarded then just died, had to replace it with my last spare, it might be related to that.
Let's stay in touch compare notes!

 

[FNTPuck]

They come rich as hell. Get a 65-70 jet kit and start at 70, dropping one jet at a time until it clears up. Depending on your altitude it will likely want a 66-68 but start high and work down.

When cold it might be slightly rich and stumble a bit, but should clear up once warm.

 

[Karl Snarl]

They come rich as hell. Get a 65-70 jet kit and start at 70, dropping one jet at a time until it clears up. Depending on your altitude it will likely want a 66-68 but start high and work down.

When cold it might be slightly rich and stumble a bit, but should clear up once warm.

this guy is most likely right. most of these engines run swell on #66-68 jet size. his advice is spot on. try it and let us know.

 

[inspectorcritic]

How is your GT5 running? What do you mean by lurching?
I got 1 rides like s**t that 3HP is not there unless they mean the horse is me.
My motor faints at any incline well not t work against gravity.
Been through 6 motors I guess in 3 years anything I order through the mail turns into s**t.
I have bought off locals 2 motors they have been the best news complaints got one in another bike happy about it the gazbike I sucker my self into I'm paying for it I'll never buy a motor from them again it's all sabotage s**t.

 

[LewieBike]

Rhythmic lurching usually means you've got the rag-joint sprocket mounted not concentrically. You might want to loosen it up and try again, making sure it rotates without being lopsided.

 

[Freddy Snottgrass]

Rhythmic lurching usually means you've got the rag-joint sprocket mounted not concentrically. You might want to loosen it up and try again, making sure it rotates without being lopsided.

Also, when my chain was too tight, I'd experience lurching. Also, my woodruff key came out my bike would lurch as the crank gear slipped on the shaft (smaller gear on the right under the clutch cover)

 

[Clats97]

I just got one too.
I went back to a NT carb on cold take off it lurches too or jerks so f***ing bad it bends the bolts on my mag drive gear guess I going to put back on my pro carb got a crooked goose neck manifold.
I found out ran like sh*t it made my CDI retarded then just died, had to replace it with my last spare, it might be related to that.
Let's stay in touch compare notes!

Text me 819 318 1671

 

[Clats97]

They come rich as hell. Get a 65-70 jet kit and start at 70, dropping one jet at a time until it clears up. Depending on your altitude it will likely want a 66-68 but start high and work down.

When cold it might be slightly rich and stumble a bit, but should clear up once warm.

I have jets. I went all the way down to 61 and all the way up to 77. Nothing.

 

[Clats97]

Rhythmic lurching usually means you've got the rag-joint sprocket mounted not concentrically. You might want to loosen it up and try again, making sure it rotates without being lopsided.

The sprocket is perfect it's a manic mechanic, chain perfect tension with half inch of play