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Discussion Starter #1
during a vinmoto outing last night a guy brought some mikuni's to sell. i told him i was interested; how much should i offer him?
according to him they were bought for his cr450 replica project by mistake and they include velocity stacks, quick turn throttle, and are jetted for a 350/450. he's throwing a fork brace in to sweeten the deal. he's saying $300.
 

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There's a guy that advertises in the AHRMA newsletter that sells Mikuni 32mm carbs for $89 each. I don't know if that includes jetting or not, I'd assume it does. Quick turn throttle figure about $50. I don't know what your guy is selling for velocity stacks but the price ranges from about $25 for why bother quality to big bucks for really well done stacks.
The phone # in the ad is 402 896 1809.

Craig
 

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Holy cow. $89 is cheap.

But if the carbs are already jetted or close to being jetted, you can save some $dough there. Needle jets are $25 each, main jets are $3-5. Pilot jets are $10 or so.... Adds up quickly.
 

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a quick hijack...

i can't find the link where people had started posting their jet settings, can anyone send me in the right direction?

also can anyone clear up for me the difference between mikuni 4-stroke and 2-stroke needle jets?
 

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quote:Originally posted by Diamondj

You can buy prepped 32mm Mikunis from Sudco or Sporting for Less for about $115 per carb.....
I'm looking to get some VM32s for my CB350. Does Sudco sell retail to individual customers? From what I can gather, their out of the box jetting "customized" for your particular application is hit or miss.
 

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quote:Originally posted by UngaWunga

I'll bet ya that those 32mm are too big for your engine. What's the stock size?
I believe the stock CB350 Keihin CV-type carburetor venturi bore is 28mm. It seems most people recommend the Mikuni VM32 for my bike. One person (whiskeysid) recommended the VM30 although that might be a typo as I thought he previously mentioned he's got VM32s on his own CB350. And it seems krapfever has either VM28 or VM32.
 

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The stock CV carbs flow about the same as 28mm slide needle carbs. You can't really compare the flow of CV vs VM style carbs because of the 2 butterflies and shape of the slide in the CVs. Generally speaking, a stock CB350 with pipes can't use more than a 30mm VM carb. A built motor can use up to 32mm VM style, if it is really built. A mildly built motor will probably be better off with 30mm VM style carbs. My motor has OEM 4th over pistons, ported head, Type 1 cam and 2-1 pipe. On a long straight I feel like it is just running out of carb on top. That is with properly jetted stock CV carbs with the choke plates removed, stock velocity stacks and uni-filters. I am going to try 30mm VM carbs. On an earlier motor in the 80's I had a built motor with big bore High CR pistons, webcam, ported motor and pipes and I used 30mm Lectron flat slides that worked well. I think people tend to over carburate their CB350s.

Ken
 

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Discussion Starter #13
the only reasons i chose the vm32's are that i have a built motor(362 thr pistons, lumpy cam, and a mildly ported head). that and the deal couldn't be argued with.
anybody need a set of uni filters and an aluminum fork brace for an sl350?
 

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Unga is right. Flat slides are gooder than round slides, but AHRMA doesn't like them.

Ken
 

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Thanks for the feedback fellas. My motor is stock so it would seem that VM32 would be too much carb for my bike. In my experience working on cars a throttle that is too large can hurt intake velocity and throttle response. My engine won't be sucking as hard as a 362cc THR kitted bike that revs to 12k rpm so I should consider going with the slightly smaller VM30 (set up for 4-stroke motor, of course). Anybody else run VM30 on the street?
 

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hey ken (aka mr. sex)
i've never heard a good reason as to why flat slide carbs are "gooder" than round and would love to learn something new. is it a small throttle response advantage or a full throttle breathing advantage...or both or neither?
-parks
 

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Parks,
I don't know the why of it all. I just "know" that generally speaking a motor that is happy with an XXmm VM will be just as happy with an XX -2 mm flat slide. I have never stuck a VM and a Flat slide on a flow bench to check it out, either.

So I am just going with Unga being right. So FU back Unga!! You can be righter than me, this time.

Ken
 

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Neither Sudco or Sporting for less sell 'correctly' jetted carbs.
They work, but only in limited rpm range.(usually for racing, at max rpm)
In mid range or fixed throttle (cruising) they are generally too rich.
From everything I've read, SFL needs complete re-jetting for road use on a CB350/360.
Out of the box they have two stroke jetting and all the brass needs changing.
I've posted a bunch of information on various sites over last 5~6 yrs.
Is there a link to the $89.00 ones?
At that price I would get some and re-jet correctly
PJ
 
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