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Discussion Starter #1
I ordered EMGO Turn out slip on pipes for my 99 Vulcan 500 and I know I'm going to need to rejet. The bike already backfires when choke isn't on during deceleration. Now I'm no mechanical genius, but I can do a lot of stuff and this seems pretty easy to do in terms of technicality but the precision work has me worrying a bit.

I've found this, http://www.jetsrus.com/FAQs/FAQ_rejetting_101_how_to_rejet.htm , which basically says adjust the idle and then the pilot screw if the idle doesn't work. That seems easy to me, almost too easy.

There are also some questions I have with this, can I rejet it with the carb still on the bike or does it need to come off every time to make adjustments if its not right the first time?

Can anyone tell me if that go by is good or if anyone has any different steps on how to do it, it would be much appreciated. I'm not really happy about the $300 I got quoted and I'd rather just do it myself to learn for future bikes I get

Thanks,
Gunnar
 

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Backfiring, or popping? A backfire is like a gunshot or a firecracker going off. A popping is more of a burbling sound in the pipes.

You shouldn't need to rejet if all you're replacing is mufflers. The bike pops on deceleration because when you close the throttle, you're making it lean, as it's still sucking air.

There are two carbs on the 500, are there not? If it's a 99, there is a good chance they my need to be stripped and cleaned anyway, and the rubber bits inspected. Re-syncing them can be a bear. If you do rejet, you may need to get a longer needle too, depending on the jet size.
here's some useful info

http://www.vulcanforums.com/forums/showthread.php?t=2413
 

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Discussion Starter #3
I think I might be wording it wrong, I'm just going to adjust the jets, not put new jets in. From what I've read, I need to adjust the pilot screw 2.5 to 3 turns out from when its completely in, personally, that doesn't seem that bad to do.

When it makes the noise on deceleration, its hard to differentiate between a back fire and pop because I wear a full face helmet, but I can feel it when it happens if that helps at all.
 

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Discussion Starter #5
Now that I have to new pipes on I actually don't feel it. I feel the normal popping during deceleration but no more big pops like a back fire.
 

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Discussion Starter #6
Since I've had been riding a lot the past few days, I noticed the popping coming back. But its under the seat so coming through the carbs. It does it at low throttle. My thoughts on this is the pilot screw needs adjusted. From what I know turn it in till its all the way seated then back it out 2.5 turns and adjust from there. My question is can I do this while the carbs are still on the bike with out the special tool?
 

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If your 500 has the PAIR valve like the 1500, you need to block off the hose. It is usually attached to the rear of the air box, that should rid you of the popping altogether. The PAIR system actually promotes the popping by injecting fresh air into the exhaust port to create the environment for popping. Thank you local EPA for that idea. It will not hurt anything and you will be happy after.

2nd I am not sure if you have the same type carb I had on my 1500, but there was a little aluminum cap that covered the pilot screw. Whe I rejetted the carb I had to slowly drill into it till it spun right off, then I had access to the pilot screw. I had to loosen the carb from the intake manifold boot so I could get to the screw then just used a precision flat head screwdriver. No special tool.

I agree though, if you are only changing pipes, you should not have to rejet.
 

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Discussion Starter #8
Mine has the CVK32 and I'm pretty sure the 1500 has the CVK36. Not sure if they're exactly the same but I think mine has those caps on it. I don't think I need to rejet, I've noticed a loss of power on the low end as it takes more throttle to start going now. I feel like if I adjust the pilot screw it'll take that away.
 
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