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Discussion Starter #1
Workin on taking out my carbs “fun fun” long story short I knocked a hole in my air box so to late to save that monstrosity so it’s cut out and out of my way. But now I really need help with jetting since there is no going back and I really don’t wanna put these back in and end up having too take them right back out. I am about 250 in elevation if that helps. All in all looks ten times better this way just trien too figure out my next step. :dead_hors
 

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Bookmarked that link, is there some kinda “understandable” chart to get the right jets? Like I said my elevation is low all I’ve ever done is replace rets I’ve never changed sizes.
I will defently looks for some good filters I’ve heard good things about k&n any suggestions for something alil cheaper to get me by till then?
Got rid of all the hoses an Just bought some (coolant bypass caps) look like they will do the job. I don’t think Arkansas has all the emission laws and checks anyways. Thanks for the response I will post my progress!!
 

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Here's a thread on my earshave/jetting experience that may be of some help to you.
It's too bad there's not a chart for jetting but it seems that all these engines are slightly different, so some of us have to experiment a little.
There are some foam unipod filters that are cheaper than the K&Ns. I bought the K&Ns before I learned of the others but I like the way the K&Ns look. If you use the K&Ns, you'll need to shim the rear of the fuel tank about a quarter inch to clear the left filter.

https://www.vn750.com/forum/22-carbs-fuel-system/102801-snow-white-plugs-after-full-ear-shave.html


*edit: I'm still running the 40/140 jets and am completely satisfied.
 

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I used Uni Pk-92's on mine, and with stock exhaust, I did NOT need to re-jet, just a mixture screw adjustment is all I needed. I am at about 15 feet altitude, so your 250 wouldnt be significantly different

for blocking off the reed valves, I used some large vacuum caps over the existing nipple of the reed valve box/cover. does same thing as removing the valve and cover and using a blocking plate
 

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Discussion Starter #6 (Edited)
So pretty much trial and error is the only way. Got a lot of tinkering to do. Is there a kit? I read that PJ Motorsports sells jets for the Keihin and I also heard that they can help get you in the ball park? Idk just hearsay thanks for the link kinda giving me an idea on what I just got myself into. Oh also the P.O. did not have one baffle so I took the other one off, considering aftermarket pipes so there’s that other monkey wrench. Thanks for the quick responses!!
 

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Discussion Starter #7
I got some caps for the reed valves not as good lookin as the coasters but still looks better than hoses everywhere
 

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Here's a thread on my earshave/jetting experience that may be of some help to you.
It's too bad there's not a chart for jetting but it seems that all these engines are slightly different, so some of us have to experiment a little.
There are some foam unipod filters that are cheaper than the K&Ns. I bought the K&Ns before I learned of the others but I like the way the K&Ns look. If you use the K&Ns, you'll need to shim the rear of the fuel tank about a quarter inch to clear the left filter.

https://www.vn750.com/forum/22-carbs-fuel-system/102801-snow-white-plugs-after-full-ear-shave.html


*edit: I'm still running the 40/140 jets and am completely satisfied.
Actually, you can just tighten the fuel tank down on the K&N pod filter and the SOB will just bend out of the way for you!
 

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I used Uni Pk-92's on mine, and with stock exhaust, I did NOT need to re-jet, just a mixture screw adjustment is all I needed. I am at about 15 feet altitude, so your 250 wouldnt be significantly different

for blocking off the reed valves, I used some large vacuum caps over the existing nipple of the reed valve box/cover. does same thing as removing the valve and cover and using a blocking plate
Any idea the 'size' vacuum cap? I'd love to get rid of the marbles I'm using
 

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So pretty much trial and error is the only way. Got a lot of tinkering to do. Is there a kit? I read that PJ Motorsports sells jets for the Keihin and I also heard that they can help get you in the ball park? Idk just hearsay thanks for the link kinda giving me an idea on what I just got myself into. Oh also the P.O. did not have one baffle so I took the other one off, considering aftermarket pipes so there’s that other monkey wrench. Thanks for the quick responses!!
BTW, my bike has been primarily driven between 300' and 350' elevation, and the 42/142 has worked well, but 40/140 probably wouldn't hurt you any either.

My friend was the P/O of my bike, and he told me that one baffle literally fell out while he was riding, and nothing on earth could get the other one out, so he sold it to me that way. When I did the goats belly removal, I finally got the 2nd baffle out with a soft block of wood, steel beam, and heavy hammer
 

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I dont remember what size off hand, I just took one of my reed valve covers to NAPA and they found one that fit.
Should be 1/2", I know a 1/2" copper pipe cap fits nice. Looked into that before I made coasters.

Elevation shouldn't be a factor with jetting until you get above 5000ft, then it needs to be leaner.
 

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I rejetted with Uni PK-92's and ultimately jetted back down. I went with 42/142, but that was so rich I could cold start it with no choke, which is not a great thing.

After about a year I pulled the carbs and jetted back down to 38/138. This is the stock pilot and 1-size-up on the main jet, and it runs much better now I think. I could smell the fuel at idle and smell it when I rolled on the throttle. Even if I didn't rejet to higher numbers I still think new jets are the way to go, those pilots are just so small and easy to get clogged with super duper hardened varnish.

Long story short, with pods I've found 38/138 to run best. (Stock exhaust)
 

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Discussion Starter #15
I had the box but I caint remember what size I bought but they fit perfect.

Took the other baffle off the other day by slightly prying the “ears?” On the baffle slid right off.

Would custom exhaust make it run lean? Theoretically?
 
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