Mikes keihin carb kit

These carb boots are the same as the BS 34s when fitting these new carbs should I also use the metal shield from my BS34 or are they OK without them?

Bobber bill,,,, I think the only problem with these carbs so far for me is that this set made it all the way to OZ with very little packing in the box there were dint marks in the box from were the carbs had been belting into the side & top of the box,,, Maore packing in the Box Please!!!!!
 
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XSLeo,

Well, I had trouble keeping my foot off the gas because it's a rush to hear those carbs sucking in the air! So, I only managed 45 MPG. I will do the run again, but try harder to control myself!
 
All I can say is thanks gents, especially Pete and Travis for the great information.

I've been looking at VM32's and VM34's plus jetting plus mounting hardware, all up the costs would be far greater than Mikes kit for the Keihins, which from the informed accounts in this thread seem to be a)bolt on and b) they work!

I will be mating these to Mikes stainless 1 3/4" headers with diodes and shorty reverse cone mufflers

I'll be ordering mine today, shame the $Oz is below parity, but it'll get back up there.

All I need now is pamcopetes ignition set up
cheers

p.s for the guys in Oz who haven't used him Mikes delivery is good and fast with tracking, I ordered the headers last week and they arrived today
 
iv got an 81' 750 big bore,polished head and high flow exhaust...would this be a good set up for my bike??i havnt got it put back together yet but my uncle said the stock carbs will not do me any good with the motor built up...and thoughts??
 
brackxs,

I bolted them on to my '81/H with EMGO reverse cone "Dunstall" replica's, which are a little restrictive, but they worked great. I just recently installed a set of MikesXS "Commando's" which are freer flowing, and there was considerable difference, especially at higher RPM's (6,000 +). Mike states that the carbs will perform at their best with a freer flowing exhaust, so I think you will really get the full benefit of your 750 with the high flow exhaust with these carbs.

However, you might want to put your bike back together with the stock carbs first so you can really feel the difference. Otherwise, you won't know if the performance is just due to the 750 conversion, and we would all like to hear what the difference is.
 
I'm running the 750 kit on my 75 with a mildly polished head, stock cam, 76 BS38 carb, K&N pods, soon to be Unifilters, 1.5" head pipes, short baseball bat looking Emgo mufflers. Runs very well. My seat of the pants dyno says about 50 rwhp now. Stock 650's are around 42 rwhp.
Pete I know how hard it is to get a good run to check milage. Awful hard to keep it at 55, wants to run 70. My last tank full got about 43, I'm guessing thats a couple mpg less than as a 650.
When I went to the Baltimore Roundup on the way home trying to out run the rain got about 40 mpg averaging 80-85 mph. Fully loaded with gear. At 50 mph I got about 50 mpg.
 
XSLeo,

Well, on a calmer day, with my '81/H and the EMGO mufflers and stock BS34's, I made a series of runs last year over the same 60 mile round trip course, trying different ignition setups and here are the results:

iridium.jpg


So, I was unprepared for the results with the Keihins. I'll try again with the Keihins, now that the novelty has worn off. I would think I could get 55 MPG if I keep my foot off the gas....:wtf:
 
Hi all,

I was wondering what the center to center spacing on the intakes is. I have an xs400 project and am shopping replacement carbs.. nobody seems to know if the 650 intakes will bolt on to a 400.

thanks,
david
 
ga650,

If you are referring to the Keihin carbs, subject of this thread, then the spacing doesn't matter as the carbs are installed individually with no mechanical connection between them.
 
Sweet thats exactly what i wanted to hear!!:laugh:I see that the kit comes with extra jets so thats nice..And i thought the same thing about install the stock ones first and then switching to the new ones...i know the originals are freshly rebuilt and ready to be installed..Thanks Pamco:thumbsup:
 
I like the idea of having one set up that works as well as it can, then make one change, like the 750 kit all I changed was the bore size. Left everthing else the same. After feeling the difference with that change, I did the exhaust. With a bit more riding to get a feel for that change, then I'll try the BS34 carbs.
Start with a base line and one change at a time. Then you can tell if the change was good or bad.
 
Just fiited my new carbs started first time zooming up the drive go's great ten times better then the old BS34s they go so great i think might hurt myself giving her to much juice.
The only problem is at idle its reving high & no idle adjustment helps so it must be a cable problem Ill check tomorrow Im going to have to get another set for my other Xs before the dlooer drops here.

Is This the same carb
keihincarbs.com/images/PWK28exploparts.jpg
 
wally,

That carb is a 28 mm version, so some of the parts may be different. The carb from MikesXS is unique and has some proprietary mods that are not available elsewhere, including the factory.

The high revs are probably due to the cable adjustment, as you say. There should be a little slack in the cables at idle so that the idle speed is controlled by the idle screws. Adjust the cable with the engine not running for equal wide open throttle position of the slides in each carb.

Once you get them all set up, you will not be able to resist cranking on the throttle to experience the acceleration. I tried to do a test run for best gas mileage, but couldn't resist winding it up, so my results were not too good. :laugh: I'm going to try again next week with a calmer riding buddy to maintain the pace! :bike:
 
Went out for run to day Im breaking up mid range it falters then picks up again, this is a rich condition is it not?
How do you replace the mains in these carbs I think i will go down one & see what happens.
 
Went down one on the main jet & goes good now , out for the day tomorrow Will see how she performs then.
I ran my cable over the top of the head between the top mount & head this gives a good straight line to the cable run.
 

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