Most likely just due to standard needles I'd think.

Mmm, does the magic CDI derestriction box fix it ?

Old Painless wrote:Mmm, does the magic CDI derestriction box fix it ?

not on this bike..

I'd be getting a new honda air filter in there and seeing if that helps.

It would be where the low speed jet runs out at a guess or does it line up with the needle changing shape ??

Right, is this any closer to what it should be?

To answer a few questions:
The Pipercross air filter foam was fitted to the bike in Nov/2003 @ 25264kms; it was cleaned about 4 months before it went on the dyno back in Aug/07 and it then had 29882kms; it's currently on about 32000kms!
I should mentioned that the chain & sprockets needed changing at the time (and still do!); that may have affected the run somewhat!? The bike was/is also running with a HRC CDI!

So if 13.5 is the optimum A/F ratio, does that mean mine's "all over the shop"? Should that waivy line across the graf be a bit more straight then? Anyone got another graf I can compare with?

Think I'll start by upping the main jets to 112 all around (does that sound right?), cleaning the air filter and changing the oil & filter plus the transmission kit, then get it back on the dyno and go from there. What should the pilot screws be set at afters? The same 1 5/8 turns out?
A standard Honda air filter might make its way back onto the bike if it shows it needs it later!
Don't want to change the needles just yet; I think baby steps are the way to go with these things, so the least I change at a time, the better!

Don't put bigger jets in - it needs smaller ones

The circular angle thing.

1/8
2/8 = 1/4
3/8
4/8 = 2/4
5/8
6/8 = 3/4
7/8
8/8 = 4/4

x3!!!
Right, so to up the jets it'll need a more free flowing air filter then? I just might take your advice on the OE filter instead and leave the standard jets in.
I think the Yamamoto can isn't particularly 'open', so that may explain things a bit!??? Damn the Jap restrictions!

On the turns subject, as the pilot screws can be quite crucial on how a bike runs, I think it could be good to clarify this for the benefit of others that may not be too sure about it either, as well as for my own sanity of course!!!

If this graffic still isn't correct, what should be on positions 1-8?


Thank you kindly for your patience!

The diagram is now correct. :)

Speedy
the chart isn't complicated its just fractions of a full turn.

for the tuning, on a next run just have them remove the filter for a run and see what happens. Your A/F suggest the upper end either could use more air, or less fuel. Either filter change, jet change or both. Seeing what happens with no filter is a good first start to see what changes, then replace with a less restrictive one if you see the change in direction you are hoping. If no change then replacing or reducing main jet is next step. As was suggested, more than age, if someone has 'cleaned' the main filters with a piece of wire they could have enlarged them significantly and not realized it.