why do people say to rejet when changing pipes? [Archive] - Suzuki Volusia Forums : Intruder Volusia and Boulevard Forum

: why do people say to rejet when changing pipes?


EazyDyz
06-30-2014, 08:17 AM
Because according to the jetting matrix, the set up for pipe change only is the same as the stock jets in my carb. Is it because the carbs are jetting differently in the UK to the USA?

mdram
06-30-2014, 08:31 AM
looking back at your intro, you have an 05 carbed model
the 05 in the us was injected.

EazyDyz
06-30-2014, 08:34 AM
looking back at your intro, you have an 05 carbed model
the 05 in the us was injected.

I think mine was built in 2004 but for some reason has a 2005 registration.
But anyway, its carbed with the same set up as every other year carved vol which is why I don't get why the jetting matrix for changing pipes is just the stock set up anyway.

mdram
06-30-2014, 08:36 AM
could be differing emission regulations allowing different jets as you mentioned in the first post.

cavie
06-30-2014, 08:38 AM
If you do have a carb, the reason for rejecting is based on pipe back pressure and air flow thru the carb. Many do nothing with the jets on pipe changes and get away with it. Depends on the pips. If you add K & N filter, you MUST rejet.

EazyDyz
06-30-2014, 10:50 AM
Is the K&N worth it? To be honest I find the power pretty nice as it is

Skrapiron
06-30-2014, 10:57 AM
The bike is lean to begin with. Changing out the exhaust exacerbates that condition and makes the bike run even leaner. The end result is a loss in available power and higher operating temperatures. Most people who don't re-jet or add a fuel processor don't realize they're producing less power.... A re-jet will restore the bike to its original power output and drop the operating temps as well.

cavie
06-30-2014, 12:05 PM
Yes, K & N is worth it. Better mid range response. Better acceleration without downshifting in most cases.

EazyDyz
06-30-2014, 01:28 PM
The bike is lean to begin with. Changing out the exhaust exacerbates that condition and makes the bike run even leaner. The end result is a loss in available power and higher operating temperatures. Most people who don't re-jet or add a fuel processor don't realize they're producing less power.... A re-jet will restore the bike to its original power output and drop the operating temps as well.

So going by the matrix logic, a 135 main jet would be best suited for a UK vol.
I get slight popping on decel at times but apart from that I can't tell the difference.

okie dog
06-30-2014, 06:31 PM
Don't know about UK vols. I got my 04 last spring. PO installed jardine flair tips. Ran fine but the rad. fan ran all the time. Always hot! After rejet , the fan only comes on every so often. My popping on decel went away after removing par valve.

EazyDyz
07-01-2014, 12:28 PM
Just been reading old threads and found the spec sheet for the USA vol.
It too has a 132.5 main jet. Looks like the jetting matrix is incorrect, as no volusia ever had a 130 main from the factory.
okie dog what did you do with regards to rejetting? My fan comes on on hot days, but i need to pull the plugs to see whats going on in there

okie dog
07-01-2014, 10:54 PM
I did the naked jugs mod, so my numbers would be different. If it is running fine but getting hot, I would just go up one notch on the main and the pilot just to be safe and its a little cold natured anyway. Rather be a little rich than lean!

EazyDyz
07-02-2014, 05:32 AM
I did the naked jugs mod, so my numbers would be different. If it is running fine but getting hot, I would just go up one notch on the main and the pilot just to be safe and its a little cold natured anyway. Rather be a little rich than lean!

Yea was thinking 135 main and just do another half turn out on the pilot jet. No point until I pull the plugs though. I'm told its normal for the fan to come on often.

okie dog
07-02-2014, 08:05 AM
Pretty sure the mixture screw is its own adjustment for the whole range. When you change out both jets, you might not want to screw it out more, it might need to go in. I've only been playing with my bike for a year. Maybe one of the experts on here will correct me if I'm wrong.