Problems on choke

[R1robo]

Hi all, ive got a problem with my 78 gs750!
Bike is starts up really rough on choke, runs on 3 to start with then slowly gets better until warm. The biggest problem is that it wont rev at all on choke, as soon as i touch the throttle it bogs down and dies.
Runs fine once off choke though!
Ive cleaned the carbs god knows how many times, changed the o rings, timing is bang on and balanced the carbs.
Any ideas?
Luke

[Agemax]

have you checked the float heights?

[R1robo]

have you checked the float heights?

Yeah checked them every time ive taken them off

[Agemax]

have you checked for air leaks? what exhaust and air filter arrangement are you using?

[R1robo]

have you checked for air leaks? what exhaust and air filter arrangement are you using?

Running pods, and exhaust is a micron full system, with the end can shortened
and the guts removed.
The intake o rings have been changed, boots have no splits. Is there any other checks to do with the air leaks?

[Agemax]

not really as far as air leaks go. what have you altered jetting wise to compensate for the pipe and pods?

[R1robo]

not really as far as air leaks go. what have you altered jetting wise to compensate for the pipe and pods?

Only the main jet, i cant remember off the top of head to what.
should i have changed the others?

[Agemax]

it really depends on what mains you have fitted, it sounds like they may be too big.
you should try a dynojet stage 3 kit to get you in the ball park, that has good start point mains and also a better tapered slide needle.

[R1robo]

it really depends on what mains you have fitted, it sounds like they may be too big.
you should try a dynojet stage 3 kit to get you in the ball park, that has good start point mains and also a better tapered slide needle.

I did go back to the standard main, and still the problem.
Im lost

[Agemax]

I did go back to the standard main, and still the problem.
Im lost

but what jets are you using???????????
you cant fit pods and a pipe, throw any old jets in and expect it to run right straight away

[R1robo]

but what jets are you using???????????
you cant fit pods and a pipe, throw any old jets in and expect it to run right straight away

ill pull them out tomorrow and have a look. 116 rings a bell though

[Agemax]

ill pull them out tomorrow and have a look. 116 rings a bell though

well 116's will be way to small then, you should be up around 125 - 130

[R1robo]

well 116's will be way to small then, you should be up around 125 - 130

Ill find out for sure tomorrow. big thanks for your help

[R1robo]

Ill find out for sure tomorrow. big thanks for your help

Got 117 in them. Thing is though its run fine with them in. This has just started to happen

[Agemax]

Got 117 in them. Thing is though its run fine with them in. This has just started to happen

if that is the case then something has changed to cause this to happen.
have you fiddled with anything or changed anything lately?
maybe you need to check your valve clearances or do a compression check to see if anything untowards has happened in the engine department.