upjetting?
 

I have an sk1 curvy with a beowulf can, and i am considerin upjetin it after the winter... if i did this would it make it less fuel efficient and by how much?
also will it make it run dirtyer and backfire more ??:P

thanks guys!
:cool:

Re: upjetting?
 

Why? If it runs OK leave it

Re: upjetting?
 

If it runs good now I wouldn't bother touching it either, a rejet is not needed for just an end can usually.

In theory a rejet should make the bike run better as the fuellign will match the exhaust, will reduce wrong time back fires considerably.

Re: upjetting?
 

haha gd points, i was just lookin for simple enough ways of makin the bike a bit faster/louder etc without startin to get into big-bore kits and the like!! (even though it is already rather loud ;-))

Re: upjetting?
 

The most effficient way to make your SV faster is to swap every single compenent for that belonging to e.g. GSXR600 ;):D

Actualy, thats a lie, but another 7 or so BHP can be afforded I think, with relativly easy mods.

If you have some trouble getting your bike running in the winter (carb icing), try using high-octane rated fuel (V-power) and/or silkolene pro FST fuel additive (origianlly formualted to help kawasaki's work in winter!).

Matt

Re: upjetting?
 

Big bore kits are expensive, even more expensive if you do it properly. The cheapest is a gearing change, add 2-3 teeth to the rear sprocket but it only improves acceleration. Or you could go down the tuning route; full system, fuelling, and cams which will get you around or a little short of 80bhp.

There is no such thing as too loud....

Re: upjetting?
 

thers a guy on fleabay makes custom stubbys for wotever size you need, theyr called 'gp xtreme' if u search that ul get what i mean and he boasts up to 18% power increase as well, im jus wonderin more what a gp style stubby wud sound like on an sv, because i wud love to splash the 200 on it after xmas jus to see! lol any experience with his gp's or any of the same style gp exhausts?

Re: upjetting?
 

The SV will not gain any power with just a slip-on.

I run the 800 with virtually no silencer (the perforated tube was replaced with a solid one) and it is loud but nice. Try running your SV on your drive with the silencer removed for a bit one day, it is a lovely noise which can be ruined by some stubbies.

Re: upjetting?
 

how did u replace the tube? i wanted to remove mine but couldnt figure out how! i know people chop and re-rivet their cans, is it a wise choice and how does it affect the legality of the can? i think in northern ireland its meant to b less than 93db but they dont really enforce that, u jus gota chose ur MOT test centre wisely

Re: upjetting?
 

I stripped the can down to pieces as it needed repacking, I went a little OTT on the dismantling. I then decided to play and rebuilt it with a solid inner pipe, it has to be sealed fully to sound good.

As long as it is still 'BS' or 'E' stamped you will most likely get away with it, don't cut the can to short or you will need to re-jet (going this short has no gain anyway).

Re: upjetting?
 

is it a straightforward drill out rivets job to take them apart, i know thers a handfull of rivets around the top of my can where the end cap is, then just re-rivet it all back together? id be scared of doin it cuz i really cant afford another exhaust right now if i mess this up haha, what does it sound like without a pipe all together, jus a big empty can?

Re: upjetting?
 

Yes

Nah... a real beast I have been told. The can is packed so it doesn't sound hollow but the inner tube is solid, it is like having a longer link pipe and no silencer.

Re: upjetting?
 

Without a pipe?

plane taking off

Re: upjetting?
 

so where or what type of pipe did you use? this is quite a noob question but i jus wana make sure i get this right cuz i cant destroy this can lol
like what material is teh pipe made from or where did u get it? etc :rolleyes:

Re: upjetting?
 

I got a piece of off cut titanium tube from a metal working/fabrication company. You will have to make a perfect seal in the pipe work at both end caps, keep the wadding in place too otherwise it sounds tinny and hollow.

If you fancy just stubby'in the exhaust do a search on here, I think Chris (yorkie_chris) may have done a step by step guide with pictures.

Re: upjetting?
 

Search a thread called exhaust tweaking.

Re: upjetting?
 

Re: upjetting?
 

Whoa so that's what my bike looks like under the muck.

Now running 165 mains. You need really big 'uns with stubby cans, or so it seems. Not as much power benefit as the jetting would suggest though.

Re: upjetting?
 

In these threads, people always say "shorties cost you midrange", and I was very skeptical but then I cleverly tested the theory, by crashing and destroying my shorty can and having to fit my unmodified can instead. And the difference was pretty unmissable in the mids. It may have lost a bit of high-end with the longer can though, that's harder to diagnose by butt dyno.

Re: upjetting?
 

Yeah that figures. Going to have another go at the straight through pipe way and see how that runs.

Re: upjetting?
 

[quote=Dangerous Dave;1639370]keep the wadding in place too otherwise it sounds tinny and hollow.
quote]

haha as an experiment yesterday (b4 i read that reply) i took the wadding out and i actually love the noise it makes, doesnt sound tinny with my beowulf, sounds like the bike without a pipe only a tiny bit quieter and doesnt make the stupid whistle sound my bike makes without an exhaust all together!!!

I think il keep it like that for a while, only problem is its making my bike run slightly too lean now, i countered that by putting the choke on the tinniest ammount... i may have to see about changin the jettin when the pays in, though i did about 25miles on it between yesterday and this mornin and its runnin alright, just if the choke isnt borederline-on the bike stalls n dies when i open the throttle

Re: upjetting?
 

What, left the perforated tube in the can too?

Won't do power much good, as I understand it you need to either run a straight through, or a packed can to stop the gas resonating about inside.

Re: upjetting?
 

yehh im considerin takin it apart again soon n takin teh perforated tube out as well, might help get the fuelin bak to normall, tho it is still running fine with the tube in! need to get some more rivets before i have another go though!! ;-)

Re: upjetting?
 

They run crap with no tube at all, just acts like an expansion chamber in reverse. Sounds naff too.

Re: upjetting?
 

haha oh right fair enuf!!

Re: upjetting?
 

+ 1

I am gonna do a trial with the 650's Akrapovic system on the 800 and see how it works, the 800 could do with a few spikes ironing out.