Adjusting carb needles

I have a completely stock SV, soon to be getting a Remus GP Revolution slip on (road legal.) I want to start meddling with the carburettors, and so I was wondering if it is worth altering the needle height, and if so, by how much? I will most likely be rejetting at some point in the near future anyway. DynoJet recommend groove 3 on their needle, same for stock?

If it's a curvy, I found raising the needle's 1 notch got rid of the slightly wooly throttle at low revs with the race can fitted.

hth

try http://www.pdq1.co.uk/ for jets.

you can get any size you want. only about 3.5 BP per set.

I think when you're going to get the carbs out, might as well rejet at once

[johnnyrod]

Raising the needle will richen the midrange but won't cure the lean top end. You can't use settings from one needle on another - they have different profiles. Get yourself a decent air filter and have the whole lot set up on a dyno - it's worth the cash and you can listen to it roaring away at the same time. I went to PDQ for my set up as it happens - top fellas.

Here's some settings that should be useful for you. I've got a Remus Gand Prix can so we should be similar.

Filter - BMC 20510R
Mains - 160fr / 157.5rr (Mikuni)
Needles - 0984h5-60v2_2.9bt (Mikuni). Set on 2nd clip from bottom.

No raising of the tank, no purchasing of a full jet kit ($$$$) no worries.

Obviously you'd likely need some fine tuning but this should get you in the ballpark. On mine it was good for another 8-9hp at the rear.

I couldn't find the jets on PDQ, only the full kits. I'm still a little unsure of what size I'm after. The DJ manual says to use part no DJ138 for an aftermarket exhaust, but as the standard size is 137.5, it doesn't quite seem enough. Or are the part numbers nothing to do with the size (which seems odd.)

[21QUEST]

Originally Posted by PeterM

Here's some settings that should be useful for you. I've got a Remus Gand Prix can so we should be similar.

Filter - BMC 20510R
Mains - 160fr / 157.5rr (Mikuni)
Needles - 0984h5-60v2_2.9bt (Mikuni). Set on 2nd clip from bottom.

No raising of the tank, no purchasing of a full jet kit ($$$$) no worries.

Obviously you'd likely need some fine tuning but this should get you in the ballpark. On mine it was good for another 8-9hp at the rear.

Which BMC filter are you using? the regular one not the full race open top.

Also bear in mind that a Mikuni 160 mains is not the same as a Dynojet 160 mains.

Cheer
Ben

[21QUEST]

Originally Posted by Fuzz

I couldn't find the jets on PDQ, only the full kits. I'm still a little unsure of what size I'm after. The DJ manual says to use part no DJ138 for an aftermarket exhaust, but as the standard size is 137.5, it doesn't quite seem enough. Or are the part numbers nothing to do with the size (which seems odd.)

See my above post for answer to highlighted text.

Just ring PDQ up. They do them cheaper than anywhere apart from ....

Cheers
Ben

[21QUEST]

Originally Posted by Fuzz

I have a completely stock SV, soon to be getting a Remus GP Revolution slip on (road legal.) I want to start meddling with the carburettors, and so I was wondering if it is worth altering the needle height, and if so, by how much? I will most likely be rejetting at some point in the near future anyway. DynoJet recommend groove 3 on their needle, same for stock?

Sorry , missed part of original post.
If you are just fitting an end can , you shouldn't need to rejet really. Stick the can on and be done. You can put it on a dyno to check but in general , it should be ok with just an end can.

Cheers
Ben

[TSM]

Convertion chart for Mikuni vs Dynojet jet sizes

http://www.ds650.net/mikunivsdynojet.htm

Acording to this sheet, 160 Mikuni are nearly the same as 170.07 dynojet