Main jets 98, but my number 4 carb has 110 ????

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z13phil
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Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Thanks in advance for any info on this . Main jets 98, but my number 4 carb has 110 ???? anyone know why.

tevan
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by tevan »

I have no reason why but if it was me I would put a correct jet in it.

CBX-tras
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by CBX-tras »

Did you MEASURE them? The other 5 might be drilled larger.

You have to check everything.

daves79x
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by daves79x »

What year/model number of carb? The VB60/61('79) has two mains, #65 and #98. The VB62/63 ('80) has #110. The VB64/65 ('81-'82) has #105. So we need to know what year/model your carbs are.

Dave

z13phil
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Ok its an A model. Whats happened to it with previous owners ???. I've owned it 2 years.
But all the the rest of the carbs jets are #98 and #65 measured these and they all check out.
But number 4 carb I have since measured this and its stamped #110 but must of been drilled it actually measures #120, this plug was always sooty !
So could these be early model carbs later fitted ? can I find a identifying number anywhere on the carb bodies. Thanks for the answers so far.

daves79x
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by daves79x »

The carb numbers are stamped on every carb - just above the split with the float bowl. But if you have two sets of mains, then they are VB60 or 61.

Dave

JoeInTUS
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by JoeInTUS »

Does your number 4 carb have a single main jet, or a primary and secondary main? If it’s a single then you have a mis-matched carb body 4.
Joe S
Tucson, AZ

z13phil
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Hi Guy's, just checked them out they are VB 60 They are all the same with two sets of mains.

daves79x
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by daves79x »

To summarize then - there is NO reason to have different jetting in one carb on any carb rack. If you are staying with stock jetting (stock airbox and exhaust), you need to get genuine Keihin jets in #98 for the secondary mains and #65 for the primary mains. Then verify what size your pressed-in idle jets are. Stock is #35, but many are drilled out larger.

Dave

z13phil
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Hi Dave, many thanks for your confirmation. So the pressed in idle jets, can I find a guide here that would explain how to remove them and the re-assembly of them. Thanks again

CBX-tras
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by CBX-tras »

Simple but special, high tensile strength, fastener to extract the pressed-in jet. Along with a short video on how-to.
Re-install with a flat punch and a machine hammer.

https://www.kmcarburetor.com/products/h ... moval-tool

z13phil
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Hi Guys, almost everything done. Just one thing ? the air screw, this has a very small washer and O ring. Now when I removed this part, They came out in this order. air screw, spring, rubber o ring, small steel washer.
Is this correct ? and does anyone know the size of the O ring, I only see them in sets with other Items i don't need.

JoeInTUS
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by JoeInTUS »

It should be mixture screw, spring, washer, o-ring. I would carefully inspect the opening for the mixture screw to make sure you got everything. On several carb bodies I have found more than one o-ring from previous rebuilds.

Randakk has individual o-rings. The size is listed here.

https://www.randakks.com/o-ring-fuel-i ... 1-1mm.html
Joe S
Tucson, AZ

z13phil
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Re: Main jets 98, but my number 4 carb has 110 ????

Post by z13phil »

Many thanks Joe.

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