bigger carbs jetting?

[Guest]

I am getting a set of 34 mm CV carbs from a forum member to go on my bored out 750. How much of a change in my current jetting should there have to be with the change in carb size?
I have a stage 3 jet kit in my current ones and I am hoping to relocate the parts to the new carbs. I am worried about the main jet air corrector, might be a pain to get them out.

[gearhead13]

No replies?

no replies eh?
The 34mm carbs are off an 1100.
Has anyone put 36mm cv's on an 1100? or 34mm on a 750?
I am wondering if my needle jet and jet needle should be swapped into the 34mm carbs. Or would they even fit?
If i need a new dynojet kit, do i get a kit for a 750 or an 1100?

[chef1366]

I put 36mm on an 1100. I run 150 mikuni mains and 47.5 pilots and ten over on the pilot air jet. (130)
I had to figure this one alone. Weird setups=trial and error. Start rich and work your way down.
How are you going to get the carbs to fit on the boots? Are you getting 1100 boots? Sixteen valve?
Good luck getting the correctors out. I tore them up with a screw. If you are putting sixteen valve carbs on an eight valve you won't need the correctors. The main air jet is already smaller.

[posplayr]

Chef

He is doing an overbored 16V 750EZ like I wanna do.

I wanna know how it works out.

Pos

[gearhead13]

I put 36mm on an 1100. I run 150 mikuni mains and 47.5 pilots and ten over on the pilot air jet. (130)
I had to figure this one alone. Weird setups=trial and error. Start rich and work your way down.
How are you going to get the carbs to fit on the boots? Are you getting 1100 boots? Sixteen valve?
Good luck getting the correctors out. I tore them up with a screw. If you are putting sixteen valve carbs on an eight valve you won't need the correctors. The main air jet is already smaller.

Is that a 150 main with corrector? I am going to try to remove them from the old carbs, if not I will sell the old ones with the stage 3 and get a new kit for the 34mm ones. Question is: do I get a kit for a 750 or 1100? What kit did you put in your 36mm's?
The 32 and 34mm carbs seem to have the same outside diameter just different inside I will find out when i get them.... They will go on somehow I hope. With as much force and lube as needed. Might work better with 1100 boots hmmmm
I am running 137.5 mains right now, I think 1 or 2 sizes more with the bigger carbs. Is it even possible to use the 750 kit's needles with the 34mm carbs? are they long enough

[chef1366]

Is that a 150 main with corrector? I am going to try to remove them from the old carbs, if not I will sell the old ones with the stage 3 and get a new kit for the 34mm ones. Question is: do I get a kit for a 750 or 1100? What kit did you put in your 36mm's?
The 32 and 34mm carbs seem to have the same outside diameter just different inside I will find out when i get them.... They will go on somehow I hope. With as much force and lube as needed. Might work better with 1100 boots hmmmm
I am running 137.5 mains right now, I think 1 or 2 sizes more with the bigger carbs. Is it even possible to use the 750 kit's needles with the 34mm carbs? are they long enough

The correctors I tried to pull out were on another bike.
I put a Dynojet kit #3133 in my 36mm carbs. (1100 & 1150) The only part I used are the needles. I would use this kit in the 34mm carbs. The needles have a large area for adjustment and you will find the sweet spot with it. Plus the 750 kits aren't made for the 34mm carbs. These kits (3133) do not come with a corrector. Do you have a corrector in the 34mm carbs? If so they are off an 8 valve and I would leave them in because the correctors make the main air jet the same size as the 16 valves. If your new carbs are off a 16 valve you don't need correctors.
I would get a set of 1100 intake boots. I have a set if you need some.
Your plugs look tan with the 137.5s? I'm not sure if you need to go up from there with the 34mm carbs. Do you have oversize intake valves and porting?

[gearhead13]

The correctors I tried to pull out were on another bike.
I put a Dynojet kit #3133 in my 36mm carbs. (1100 & 1150) The only part I used are the needles. I would use this kit in the 34mm carbs. The needles have a large area for adjustment and you will find the sweet spot with it. Plus the 750 kits aren't made for the 34mm carbs. These kits (3133) do not come with a corrector. Do you have a corrector in the 34mm carbs? If so they are off an 8 valve and I would leave them in because the correctors make the main air jet the same size as the 16 valves. If your new carbs are off a 16 valve you don't need correctors.
I would get a set of 1100 intake boots. I have a set if you need some.
Your plugs look tan with the 137.5s? I'm not sure if you need to go up from there with the 34mm carbs. Do you have oversize intake valves and porting?

I have a 3mm overbore for 816cc and a mildly ported head, with new cams to come later. AS far as I can tell, the carbs are off of an 1100 2 valve. They havent arrived yet. How do I tell if there is a corrector in them already? Like a factory one?
With the plug chops I have done, the main is very close, I am just messing with the needle right now and waiting for pilot jets
There arent a lot of open roads to do a high rpm plug chop around here. Could go one main size higher maybe.
I ordered pilot jets from bike bandit, said they were sold in sets of four, They shipped me ONE of each size

[chef1366]

The correctors are the brass thingys that are tapped into the main air jet. Stock are what they are.
The eight valve carbs have a larger main air jet. This is the jet on the filter side directly opposite of the screw in pilot air jet. They are set in the body so that's why the correctors are needed. The correctors actually make the main air jet smaller.

[gearhead13]

The carbs I recieved are mikuni part# 49220 off of an '82 GS1100EZ as far as i can tell from a search on the forums.

http://www.thegsresources.com/_forum/showthread.php?p=292078&highlight=49220#post292078

My 750 intake boots fit fine for some reason
I dont know if I can afford the dynojet kit right now, so I was thinking of installing them with my airbox for now. Unless the needles from my 750 kit fit

[gearhead13]

He is doing an overbored 16V 750EZ like I wanna do.

I wanna know how it works out.

Pos

If you can afford the piston kit and bore, I would say go for it! With stock cams and midly ported head, the torque peak moves down into the midrange more, with still plenty of top end power available. Lots of highway roll-on power. I am enjoying the extra midrange right now and I am looking forward to getting aftermarket cams for it.

[gearhead13]

I was checking my plugs a couple days ago and plugs 1&3 were a lot darker than 2&4. I also have a misfire at cruising speed, so I went and ordered a set of dyna coils for it. The coils and carbies should give the bike some more grunt
Gonna be an exciting week

[chef1366]

I was checking my plugs a couple days ago and plugs 1&3 were a lot darker than 2&4. I also have a misfire at cruising speed, so I went and ordered a set of dyna coils for it. The coils and carbies should give the bike some more grunt
Gonna be an exciting week

Do not try to jet or tune a bike with the stock ignition. It is a tail chasing nightmare. Get a Dyna S and Dyna green coils.
I almost burnt a head tuning lean with a weak ignition.

[gearhead13]

Do not try to jet or tune a bike with the stock ignition. It is a tail chasing nightmare. Get a Dyna S and Dyna green coils.
I almost burnt a head tuning lean with a weak ignition.

The bike already has electronic ignition, I dont really see the benefit of the dyna s, all it has to do is create a pulse at the right time, doesnt matter if the pulse is stronger or not. The coils I am getting will give it more spark at the plugs, so it will ignite the mixture better.

[chef1366]

The bike already has electronic ignition, I dont really see the benefit of the dyna s, all it has to do is create a pulse at the right time, doesnt matter if the pulse is stronger or not. The coils I am getting will give it more spark at the plugs, so it will ignite the mixture better.

OK it's your call but the stock igniters suck a$$.

[gearhead13]

Those coils and carbs REALLY woke up the bike. TONS more power. Went for a ride late last night after I was done.
Thanks for the help in figuring out the carbs.
They came with a 47.5 pilot jet which seems just right.
I am getting some bogging when opening the throttle at lower rpms, need to raise the needle maybe.