Topic: Have a set of 38mm GS1100 Mikuni BS CV Carbs laying around.... spacing is right.

[TCSOHCB750CAFE]

Wondering if there is any experience running these carbs on a CB750 sohc? I don't have any figures, but obviously they would allow a lot more air past that slightly larger venturi

Just wanted to see if anyone had any issues, success, anger, happiness, etc. with this setup before I go sticking it on there.

Thanks.

[Retro Rocket]

Interesting. Is your bike modified? probably too much carb for a stocker. Stick them on anyway i would like to know how well  they work..

Mick

[TCSOHCB750CAFE]

Will be doing a cam, pistons (KZ650's since I've got a lot of them around... I'm a KZ nut.) The KZ650 pistons increase displacement and raise compression. Did the math and interchange lists and it looks like they should work out great. Also will be building an external jet system like cycleXchange sells for $220.00. (I don't pay for something I can build with the mill at work. ), maybe springs, valves, etc. I dunno how crazy I intend to go with this. I love the CB, don't get me wrong, but no amount of work will financially be justified trying to make it a real monster when I've got other bikes that are a significantly better starting point for a real monster.

I've basically just got this project headed up cause it's a place to put a lot of the spare parts that I've collected over the years. haha



That's where it left off.

Just figured out what bearings I need and did some machine work on the stem today to run a GSXR 750 fork on it with the GSXR stem.

Next step is retrofitting the GSXR rear end, then worrying about the mill.

If anyone else has experience on this setup wether modified or stock, let me know. Thanks!

[Retro Rocket]

Well i have a GSXR 1100K front end on mine and a cut down GSXR1100 swingarm with twin shock mounts. Also a 1000cc 10.5 to1 piston kit, billet aluminum block with nikasil bores, RC crank and rods {carrillos coming} ported head with oversized valves with all the goodies, back cut gearbox , heavy duty timing chains, megacycle cam, barnett clutch, anyway thats why i am interested in the carbs....
Screw the money, you only live once.....

Mick

[sander]

I have tried to fit a set of mikuni bs33 carbs and they won't fit the stock boots. They will hit the toptubes of the frame. It might work if you made new boots.
After i finish my bike and have it running, i'll give it another try.

[Sam Green Racing]

I think you will be over carbed. 34mm is about maximum and that's with some serious porting and trick valves. Think about the size of the hole at the other end of the inlet tract.

Sam.

[mick7504]

Years ago, a friend fitted some huge carbs onto his 750 (modified) and said that down low, it was a real pig.
Lots of spare cash will get a set of these Mikuni TMR 32's.
$2295:00 USD.
Bloody nice and bloody expensive.
As Sam said, 34mm would take it to the edge.
Mick

[MRieck]

Years ago, a friend fitted some huge carbs onto his 750 (modified) and said that down low, it was a real pig.
Lots of spare cash will get a set of these Mikuni TMR 32's.
$2295:00 USD.
Bloody nice and bloody expensive.
As Sam said, 34mm would take it to the edge.
Mick

They are nice Mick.....I've got a set in my shop.

[754]

Those carbs shown, do you have to srew around with float level or mod them?

 I dont have a calculator handy.. but plug in 14mm X pi, then square that total..then do it with 19mm.. then you will see the diff in throat area.. it will be large.
 With Webers the diff between 30 mm and 32mm throats, is quite noticeable in the amount bottom end will suffer.

 Having a bike that is only fun to ride when revved up high, is not that great on the street.. real ticket bait..

[Retro Rocket]

Years ago, a friend fitted some huge carbs onto his 750 (modified) and said that down low, it was a real pig.
Lots of spare cash will get a set of these Mikuni TMR 32's.
$2295:00 USD.
Bloody nice and bloody expensive.
As Sam said, 34mm would take it to the edge.
Mick

They are nice Mick.....I've got a set in my shop.

Would it be possible to run a modified air box with those? Do they {TMR's} have an accelerator pump?
That would help with low end power wouldn't it?

Mick

[mick7504]

Years ago, a friend fitted some huge carbs onto his 750 (modified) and said that down low, it was a real pig.
Lots of spare cash will get a set of these Mikuni TMR 32's.
$2295:00 USD.
Bloody nice and bloody expensive.
As Sam said, 34mm would take it to the edge.
Mick

They are nice Mick.....I've got a set in my shop.

Would it be possible to run a modified air box with those? Do they {TMR's} have an accelerator pump?
That would help with low end power wouldn't it?

Mick

Mick
Here is some more info about the TMR's.
http://www.motorcyclecarbs.com/Mikuni_TMR_Carburetor_C1817.cfm

[Retro Rocket]

Didn't see much info in that link mate but i did a search and found out most of what i needed to know. So, does the accel pump fix the low end grunt {or lack thereof} problem..?

Mick

[mick7504]

Didn't see much info in that link mate but i did a search and found out most of what i needed to know. So, does the accel pump fix the low end grunt {or lack thereof} problem..?

Mick

Mate, Being quality Mikuni and specific for the application, you would expect these carbs to raise the bar and either minimise or elimiminate any low end issues as well as greatly assisting in peformance gains.
Mick
 

[Sam Green Racing]

I wonder if Murphy will have this low end grunt problem when he sticks his TMRs on his trillion $ CB

think not

Sam.