VZ800 Jetting question

Hi, I notice there's a post from back in 2013 put up as a guide to jet sizes for various configurations. I'm a bit confused by it, I've a 1999 VZ800 and on it the front and rear carbs are fitted with different size jets, the guide doesn't reflect this, or am I missunderstanding the guide, anyone able to clarify or alternately, anyone have experience fitting a stage 2 jet kit I'd love to hear from you? Cheers.

Different sized jets front and rear seems to be normal on the VZ.  A little bit of home work for you http://home.wyan.org/~jrhdlh/jetting.txt

Yep, my 97 VZ has 100 in the front, and 90 in the rear.

hmac wrote:

Different sized jets front and rear seems to be normal on the VZ.  A little bit of home work for you http://home.wyan.org/~jrhdlh/jetting.txt

Thanks hmac, must be an omen, found this same link last night myself while googling down the back of the internet and ordered some jets based on what I read.

Originally tackled this using a kit I bought from the US but going by the direct experience of the guys who've posted that info, the kit is out by as much as 30...recommendation was 95/105 just 5 up from stock, what's needed for my set up (Straight through 50mm Highway Hawks/K&N SU5589's box mounted high flows) is around 122.5/132.5 - 125/135.

I'll post again once I've tried the larger jets and let you guys know how it goes.

Thanks guys for your replies, good to know this is such an active forum,

Let us know how you get on, I'm tempted to do mine.

Are you the owner of  the  Marauder with the custom paint job I met at the Alba West show?

I'm impressed, how did you figure that out? Yes, how you doing, still haven't moved forward with the back end job I wanted to do so still looking at yours with envy. I'll defo post how I get on once I've got the bike up and running, what drove me down this path was that the bike won't run with straight through pipes on the stock set up...or at least mine won't, just overheats with being way too lean. Gutted, thought it was all ok back in October, wasn't until I got it out on the road and above half throttle that I realised there was a big problem...or as it looks a too small jet problem, still it's the joys of biking eh. All ok with you and yours, nice to hear from you in any case?

Not many Marauders in Scotland, apart from ours I've only seen three. When I saw your handle and that you were in Scotland a wee bell rung and I remembered speaking to Brian Holmes at  the Alba West. Not done much to the bike since you saw it, been enjoying riding it too much.
Did you do anything about forward controls? You spoke about getting something like mine made up.
Maybe see you at Alba or some of the other rallies over the summer.

hmac wrote:

Not many Marauders in Scotland, apart from ours I've only seen three. When I saw your handle and that you were in Scotland a wee bell rung and I remembered speaking to Brian Holmes at  the Alba West. Not done much to the bike since you saw it, been enjoying riding it too much.
Did you do anything about forward controls? You spoke about getting something like mine made up.
Maybe see you at Alba or some of the other rallies over the summer.

...thought I was Sherlock! Yeh, you're right you don't see many going around. 

Naw, likewise not much changed, got close to rear end mods, had the mudguard off for cloning by a friend who's into fibreglassing, didn't happen though, he moved up to the 21 and found he'd no time too himself so it got bunged back on. Forward pegs I decided against, in the cold light of day I realised I need to be about four inches longer in the leg to justify it. Probably end up with something different but not forward, just for looks. 

Hoping the new jets arrive tomorrow so I can give them a try and hopefully get up and running. 

You ever do the Leadburn Thursday nights?

Just a quick post. Received and fitted a 125/135 main jet pair today, absolutely no issues at an point through the full throttle range, short run as no MOT so don't know what the top end is like, but was still accelerating through 90 when I backed it off. Extra oomph can't be missed and detected no flat spots, all looking good. Will put up a full post with all the details once I've put in a few miles and checked plugs etc. 

Happy biker.

Sounds like you got a good result with those jets. What gearing are you running? I found the stock setup way undergeared, so I  got rid of the 15 tooth front sprocket and replaced it with a 17 and kept the standard 48 rear. Really made a difference to the bike, still accelerates well and the engine is a lot less stressed at motorway speeds. 

One advantage for me having the forward pegs is I no longer leave a trail of sparks at every other roundabout, might be worth looking at raising yours an inch or two.

Not been to the Leadburn yet, probably take a trip over there one fine summer evening.

I'll take a look at the sprocket sizing, if you decide a trip to the Leady, first Thursday of the month is the big one, that's the night they have trade stalls and the like, drop me a line if you're coming and I'll treat you to a coffee.