Best carbs for GS1000

[Wraith]

Hi all,
I'm starting to put my old GS1000 back on the road (been a long time project LOL) it has a tuned motor and I'm looking at two tipes of carbs.
One set is the GSXR750 36mm the others are the GSX1100efe 36mm which do you all think are the best for the GS1000?

Cheers

 

[winfield]

Let's get the smart alec response out of the way right up front.

(clearing throat)... stock

 

[hampshirehog]

The ones from the Gixxer.

 

[Wraith]

Let's get the smart alec response out of the way right up front.

(clearing throat)... stock

Yes, that's one point of view. However, in my defence my '1000' is not exactly "stock": 1100cc Wiseco kit/bores, fast road hi-lift cams, ported/flowed head, race zorst, individual air filters and, well, loads of other bits.
Original carbs 26mm slide or 32mmCV. Somehow I think that they may have a tad of trouble dealing with all of that

I was running 35mm CR Keihn roundslides, but although they gave huge amounts of performance (power delivery, hyperspace drive, etc) they were a bitch riding through traffic - or slowly in any conditions for more than a few minutes - and a bike which already isn't exactly frugal on fuel consumption went down to about 15mpg - which here in the UK is now requiring several bankers' bonuses to fund

So I'm looking for a carb set which still let me have a reasonable performance without the hassle in traffic or the fuel greed. I live in a rural area where there's not many fast or straight roads (at least, not long stretches of them), so a lot of on/off throttle work, bends, corners and hills and a fair few bits of lower speed villages/small towns and then stretches of rural roads again. Accordingly it's really more working with torque and acceleration than utter top end and someting which will work as a reliable carb throughout the full range of idle/pilot to fully open (and back again), on-off repeatedly and rapidly.

 

[Agemax]

get some VM28SS from a GS1000S, or get some VM29SS from early GSXR750 and bore them out to 33mm

i run VM28SS on my GS1085 with belmouths, and it is perfectly tractable on the road and fuel consumption is pretty good

 

[winfield]

Yes, that's one point of view. However, in my defence my '1000' is not exactly "stock": 1100cc Wiseco kit/bores, fast road hi-lift cams, ported/flowed head, race zorst, individual air filters and, well, loads of other bits.
Original carbs 26mm slide or 32mmCV. Somehow I think that they may have a tad of trouble dealing with all of that

I was running 35mm CR Keihn roundslides, but although they gave huge amounts of performance (power delivery, hyperspace drive, etc) they were a bitch riding through traffic - or slowly in any conditions for more than a few minutes - and a bike which already isn't exactly frugal on fuel consumption went down to about 15mpg - which here in the UK is now requiring several bankers' bonuses to fund

So I'm looking for a carb set which still let me have a reasonable performance without the hassle in traffic or the fuel greed. I live in a rural area where there's not many fast or straight roads (at least, not long stretches of them), so a lot of on/off throttle work, bends, corners and hills and a fair few bits of lower speed villages/small towns and then stretches of rural roads again. Accordingly it's really more working with torque and acceleration than utter top end and someting which will work as a reliable carb throughout the full range of idle/pilot to fully open (and back again), on-off repeatedly and rapidly.

My smart alec answer wasn't worth you responding to it. I just couldn't keep from typing. I don't know why sarcasm comes so easily to me.

Your bike sounds like it will be a lot of fun. Do you have a GoPro? I sincerely would love to see a video of a ride through the countryside you describe.

 

[Steve]

Winfield may not have been as far off the mark as he thought. :-k

The stock carbs on the '80 GS1000 were BS34, not BS32. The 1100 also used the BS34, the 1150 used BS36.

I would think that for street use with the occasional "blast", the BS34s might work quite well.

.

 

[Guest]

I would think that for street use with the occasional "blast", the BS34s might work quite well.

Sounds like great advice, as usual

 

[tkent02]

I rode a GS1100E with the GSXR carbs, it was really carbureted well. A ton of power and great gas milage. It may help that the owner was a very good mechanic and spent a lot of effort getting them perfect.

 

[Guest]

I rode a GS1100E with the GSXR carbs, it was really carbureted well. A ton of power and great gas milage. It may help that the owner was a very good mechanic and spent a lot of effort getting them perfect.

Yeah, Mikuni 36MM smoothbores on my gpz900/1000 and they seem to do great.

 

[winfield]

Winfield may not have been as far off the mark as he thought. :-k ...
.

Well, even a blind squirrel sometimes finds a nut...

I just wish he would find the dang bolt that went with it too.

 

[chuck hahn]

Steve got the years and sizes right. My 79 came with 29s that i sold and put the stock 26s on. And I now have a set of the European size VM28s...I like stock configured bikes though.

 

[gs11ezrydr]

I got a good set of BS34's for 100 bucks PM me and let me know what you think. I was going to Ebay them soon. Seen them going for $175-$225 depending.Stock slide lift holes never drilled for a dynojet kit like most have been. Well kept and *Clean* (Firm)

 

[Wraith]

Cheers all, (this is why I like this site lods of addvice ) I have not got the stock carbs, so as I do have the GSXR ones and some of you say they work I will give them a go
At the end of the day I can always have a play over the summer swopping carbs
I don't know what a GoPaly is? but when the wether gets better I can do a vido of a ride around the lanes but I want show the speedo you dont know who is looking LOL

 

[sharpy]

However, in my defence my '1000' is not exactly "stock": 1100cc Wiseco kit/bores, fast road hi-lift cams, ported/flowed head, race zorst, individual air filters and, well, loads of other bits.
I was running 35mm CR Keihn roundslides, but although they gave huge amounts of performance (power delivery, hyperspace drive, etc) they were a bitch riding through traffic - or slowly in any conditions for more than a few minutes - and a bike which already isn't exactly frugal on fuel consumption went down to about 15mpg - which here in the UK is now requiring several bankers' bonuses to fund

So whats the HP you think at rear wheel?

 

[Tarbash 27]

Mikuni 29mm smoothbores or 33mm smoothbores on a big port head, thats what i run.

 

[Steveb64]

I'd agree with Tarbash. My old GSX1100ET/X was tweaked a bit - Yoshi 1135, Yoshi stage II cams - which got 'updated' to an unknown brand with more lift and a LOT more duration, handmade exhaust, K&N pods, and it ran really nicely with a set of 33mm Keihin CR Specials (smoothbores). Back in the bad old days (pre speed cameras, lasers, etc - 30 years ago ) , when we could still 'cruise' at 130-140-160 kph and not get busted - or lose our licences, I used to get slightly better mileage than my mate did with his stock GS1100G (shaftie). About a litre less per refuel - at the same mileages ~ 150-180 kms. I had some 37 mm Keihins for it that I tried for a while - but I could never get the damn things jetted up right, and ended up going back to the 33's.

You know that you can unscrew the front spigot of the CR's, and replace it with a smaller inner diameter? Then you could change your 35's to 33's... You may need (probably) to change the needles though (lean the upper range a bit from what the 35's are set to)... as well as some other jetting.
Someone had done that to my 33's - and made them 29's - but hadn't changed the needles. Which made them run like pigs... A mates old man who was a watchmaker by trade made me up some new ones on his hobby lathe at home - did a beautiful job on the threads - and I fitted them in. ... is all I can say.

 

[Wraith]

So whats the HP you think at rear wheel?

I dont know what the BHP is with the 1100cc kit, but when I was running the CR35mm carbs I had Kwak GPZ1170 pistions in it 78mm I think (which made a 1148cc big bore on the GS) and it was giving me 118BHP at the rear wheel but I had spent over ?2000 on the motor. It was grate on the strates lodes of power and would go strate upto 150mph in a blink but since then and now got a chain drive as this was on the shatf I've been doing a bit of swoping about and gone down in cc and back to CV carbs on the shaft to make it a bit better alrounder and started bulding a chain driver motor with the nice bits

Why, why not LOL

 

[Wraith]

You know that you can unscrew the front spigot of the CR's, and replace it with a smaller inner diameter? Then you could change your 35's to 33's... You may need (probably) to change the needles though (lean the upper range a bit from what the 35's are set to)... as well as some other jetting.
Someone had done that to my 33's - and made them 29's - but hadn't changed the needles. Which made them run like pigs... A mates old man who was a watchmaker by trade made me up some new ones on his hobby lathe at home - did a beautiful job on the threads - and I fitted them in. ... is all I can say.

Yes I know thanks, I like the 35mm as they can give a big increase over the 33mm but the 35mm can be a pain to set up
I have had te GS1000g for about 20 years and it was my first GS1000 and I had done a lot of work on it over the years (it did start life as a GS850g LOL) and I must say its been off the road more than on over the last 10 years and as I want to use it more day to day I'm detuning it abit but buidling a chain drive motor for te other GS1000

 

[Steveb64]

Yes I know thanks, I like the 35mm as they can give a big increase over the 33mm but the 35mm can be a pain to set up
I have had te GS1000g for about 20 years and it was my first GS1000 and I had done a lot of work on it over the years (it did start life as a GS850g LOL) and I must say its been off the road more than on over the last 10 years and as I want to use it more day to day I'm detuning it abit but buidling a chain drive motor for te other GS1000

Lol - sounds like you've got your workshop time all booked for a few more years...
I've still got my GSX (bought it in '83) - looking kinda sad, stuck in the back of the shed for now. One day I'll drag it out (If my new business plan works out, I'll be able to afford to), and get it back in action again - but as a post-classic racer. Then the next project will be the bike in my avatar - which is also GSX11 powered. <sigh> One day...
BTW - I got my 1100 (well 1135) to do a SS1/4 in 11.1 secs, and a timed 'flying 1/4' average (it was still accelerating through the 1/4 - with an 800 metre run up) of 143mph. And that was with a 1 tooth smaller front sprocket on it, for the SS1/4 runs. Gave a few of the guys with new bikes a big fright.
And I used to use it as my regular ride. Actually, it was rather civilised, given the cams and bits that were in it. Even idled OK. Lumpy, but an idle.