Does anyone know if Dynojet size their jets different to the std Keihin ones??

My NC29 race bike has 108 (Dynojet) mains in it but is still running rich (tailpipe was still black and sooty even after an 8 lap race at Olivers Mount)

The bike has GF airbox with ram air, K + N filter, tuned motor and Beet copy exhaust.

I was thinking of getting one of Yakama's HRC carb kits, but the jet sizes in these are massive - are these designed for running with no filter?? I would prefer to keep the filter as the road circuits tend to be a bit dirtier than closed circuits.

Cheers

Tony

Yes dynojet jets do flow more than Keihin, its been covered a few times and i think theres a chart somewhere.

As for yakama's HRC kit dont quote me but im sure your need to run a full HRC setup for it to be of any use.

The HRC set up I'm selling is designed to work with the HRC airbox (which I assume you have if you have a GF copy) and HRC CDI and an HRC exhaust. It comes with a range of needles and so shoulw suit various set ups

And sorry yes is designed for no filter though I'm sure sone sort of thin filter could be used without compromising the setup too much

Simply fit the HRC air filter set up ... and clean out the air box everyday.

Check the air corrector blanks are still in place.

Or carefully clean and very very lightly re oil the KN .. use KN cleaning kit.

108DJet should be good .... very very occasionally we have used a 106 on a Ram Air set up ... with air corrector blanked.

Hope that helps.

[quote="tfr125"

My NC29 race bike has 108 (Dynojet) mains in it but is still running rich (tailpipe was still black and sooty even after an 8 lap race at Olivers Mount)

Tony[/quote]

Unless you are running Avgas which is a leaded fuel your exhaust will alway be black and sooty, this is the way unleaded fuel burns. My bike has been set up on a dyno and the fueling is nearly spot on and the exhaust is black and sooty. I have however found out where I can buy avgas from a bowser wit a credit card after hours.

Matt

The plugs are a different story though, check them.

Matt

Thanks for all the advice guys.

I am used to running two-strokes and have a bit of experience of using unleaded and avgas fuels. The two stroke tailpipes with unleaded were always black compared to the avgas , but the pipe on the NC29 is not only black but has soot all around the inside and outside of the tailpipe!! I will have a look at the plugs though and see what they look like.

Probably the easiest solution is Graham's suggestion of the HRC filter (am I right in thinking this is a standard filter with all the paper filter removed leaving just the mesh??)

Thanks again

Tony

Tony,

Correct re the HRC filter set up ... I still remember ordering 2 new some years back from Padgetts ..... quite a shock on price !!!

Be careful not to break any of the mesh retaining "rivet" points.

Cheers

Graeme