Help deciding between these carbs

Firestorm102389

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Stock 1982 XS650, putting it into a buggy I'm building, stock engine, other than exhaust. I've been digging into carbs, as the ones that were on the bike when I got it aren't any good anymore. Anyway, lots of information out there, but there are gaps and missing info. So here are the carbs I was looking for info on, other than the VM34, I found plenty, but it is one i'm considering. Power jet style I just happened to notice one on amazon and it seemed a lot like the mikes PWK carbs. The pumpers are what I'm interested the most in, the way they operate sounds like it would be a much smoother accelleration no matter how fast or slow I hit the throttle. Important mention: I'm going to be making an intake 2-1, i have made one before for another bike, so i know how it works.

Standard style:
VM34 Mikuni Carb (Lots of info i've seen on here, no need to elaborate)

Power Jet style:
Nibbi PWK34 power jet (Curious if anyone has run one, how does it work. they look nice, but not if they don't perform, seems similar to mikesxs PWK)

Pumper/ accelerator Pump style: (Very Interested in these)
Mikuni tm33-8012 flat slide (slightly Smaller pumper)
FCR 35MM from JFG Racing (Slightly larger pumper, 35mm)
Dellorto PHF 36 (Looks like it could be an amazing carb)


Ok, so the meat and potatoes of the subject.
1) Those of you who have physically had them on your bike, and tried them, I'd love your input! Which did you have, were they relatively close in settings, or did you have to
make major changes?
2) I know someone on here had the TM33 and TM35 pumpers, would be great if he is still here to let me know how well they worked
3) I'm assuming the dellorto PHF 36 has been used, it is a pretty easy one that comes close? I can swap jets, and needle clips, but that's as far as my knowledge goes.
 
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I put VM 34s on my 74, turned up longer intakes to clear the taps, swapped the taps around and also turned up pancake filters to clear the air. No carby conversion is going to have the right jetting straight out of the box, but I can't of anything easier than jetting a carb, maybe pumping up tyres?

I chose Mikunis because they are simple, better than those BS rubbish things, work well and jets and parts are readily available.
Just be aware the VMs will sit right under the taps so the cables will interfere with the taps. The only way around that is to either angle them inwards, use longer manifolds or use BS34 manifolds. There's a 2mm difference between VM34 spigots and BS34 spigots, but the manifolds being rubber can be snugged up a little to take up the size difference.
Don't know about the others, but I would assume they would all have their pitfalls as far as fitting is concerned.
 

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I will edit the original post, the motor is going in a custom buggy I'm building, so I don't have the clearance issues of it being in a motorcycle.
And yes, the VM34's are nice and simple and those will be my fallback if I can't get the info. At least until I get money together to buy a different one to test out.

What intake is that you have on there?!
 
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The VM cables interfere with the petcocks, I'm not one to bodge up a fit by angling the carbs over to clear the taps, So I turned up a couple of longer manifolds to site the carb cables behind the taps.
Most of the XS650 parts outlets have kits for the VMs, the kits come with manifolds, cables, extra jets and clamps. Being as the motor isn't in a bike, the manifolds should fit ok
 
The VM cables interfere with the petcocks, I'm not one to bodge up a fit by angling the carbs over to clear the taps, So I turned up a couple of longer manifolds to site the carb cables behind the taps.
Most of the XS650 parts outlets have kits for the VMs, the kits come with manifolds, cables, extra jets and clamps. Being as the motor isn't in a bike, the manifolds should fit ok
yeah, i know, I just like the simple design of having 1 carb. no syncing necessary, and cheaper as you only have 1 carb to buy parts for.
 
You can't beat a single carb for a day to day rider, it makes riding more enjoyable, power is less at peak revs, but who rides around the streets at peak revs? Engine develops torque lower in the rpm range making it more ridable. Of course, the differences are miniscule and you'd be hard pressed to notice the difference without a stop watch.
 
You can't beat a single carb for a day to day rider, it makes riding more enjoyable, power is less at peak revs, but who rides around the streets at peak revs? Engine develops torque lower in the rpm range making it more ridable. Of course, the differences are miniscule and you'd be hard pressed to notice the difference without a stop watch.
This is a good answer, if i'm not going to notice the difference much, then i'm not gonna spend the extra cash right now anyway. I'd still be interested in hearing about the other carbs if anyone has tried them sees this thread, because I'd still like to try at least the dellorto later.
Most of my riding is usually around the mid range, only time I think i'd need the top end, would be for passing power, or that seat of the pants feel of accelleration, but that I can also get from sprocket gearing.
I'm sure dialed in, they work just fine, otherwise there is a power jet kit I saw that people can install, which would help the WOT issue you're refferring to.
 
I ran PWK’s (probably from Mike’s) for half a season when I first got my bike. At the end I got it to run ok but took constant fiddling and lotsa of jet changes. it would run well above idle but would foul plugs with extended idling. Bought a pair of stock BS38’s and never looked back. Best performance? Perhaps there’s better but now I’m not adjusting the carbs all the time.
 
I ran PWK’s (probably from Mike’s) for half a season when I first got my bike. At the end I got it to run ok but took constant fiddling and lotsa of jet changes. it would run well above idle but would foul plugs with extended idling. Bought a pair of stock BS38’s and never looked back. Best performance? Perhaps there’s better but now I’m not adjusting the carbs all the time.
I had a chance to score some PWK's cheap, and the late Dick Russell told me "I wouldn't touch them with a ten foot pole". 'Nuff said.
 
well, I will say this. I had an xs400 that I bought the mikes kit for, and I got them to run absolutely beautifully despite everyone on THAT forum saying they were junk. Yes, they are harder to tune, yes I purchased the 650 kit by accident but they assured me it was only jet changes (Not true). The slides cutaways are different, which i didn't find out till next riding season. They don't know their product that well, but when I purchased the right cutaway, It was much easier to tune and it ran fantastic.
I had thought about buying 1 to use on this, but I wanted to spend the money on a pumper carb to try out, and it doesn't appear to have an option to purchase 1 carb outside of buying the kit with 2. So, I'm going with the VM34 for now, and I'm gonna try a pumper carb later to play with and see which I like more.
I still would love to hear from those that have tried any listed as they are all ones i've considered still getting to play with. (I like to tinker)
Love the input so far, and Pumper carb input greatly appreciated aswell. I Want to wrap my mind around it!
 
I think the Mikuni flat slides are available with a pump. Personally, I wouldn't go past a Mikuni...
 
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