Dynojetting an early R1

[exuprob]

Ive got '99 4xv R1 which is pretty much stock except for a carbon end can (Akro) and a K+N filter in the stock airbox.

I fitted the Dynojet kit exactly as the instructions stated which included new needles, new slide springs and 134 mains but having been out for a spin it feels better in the midrange but seems to run out of puff higher up.

The Dynojet instructions say 'If you have a race exhaust and a free flowing airfilter then fit the 134 main jets' so I did but should I try the 132's that also come with the kit to see if it helps?

Bit worried about running it lean

Fitted one of these to a '99 ZX6r and it was fit and forget, not so with the R1 then?

Any help greatly appreciated.

[budda]

Ive got '99 4xv R1 which is pretty much stock except for a carbon end can (Akro) and a K+N filter in the stock airbox.

I fitted the Dynojet kit exactly as the instructions stated which included new needles, new slide springs and 134 mains but having been out for a spin it feels better in the midrange but seems to run out of puff higher up.

The Dynojet instructions say 'If you have a race exhaust and a free flowing airfilter then fit the 134 main jets' so I did but should I try the 132's that also come with the kit to see if it helps?

Bit worried about running it lean

Fitted one of these to a '99 ZX6r and it was fit and forget, not so with the R1 then?

Any help greatly appreciated.

Is it an old dynojet kit mate, I seem to remember that they came down a size on the jets on the later ones.

I was told that the jets are oversized, and will run better with the smaller ones so give it a try.

You've nowt to lose............Good luck.

[fran9r]

http://www.allensperformance.co.uk/

For when those needles wear the needle jets!

[trackdaybob]

To get the full benefit of the kit you need a race exhaust system not just an end can. Although you're getting more fuel and air in the standard downpipes & exup can only flow so much hence the 'strangled' top end. Try the 132's they may suit your set up better.

Have you had it on a dyno? A bit of dyno time and a skilled operator will show up exactly what the problem is. Dyno time isn't always cheap but almost always worth it.

My 4xv has a full Akrapovic ti with carbon can, K&N and a Dynojet kit. I can't for the life of me remember what mains I'm running but I can tell you after some dyno time it's pumping out 144bhp @ the wheel.

[Doug_R1]

I only fitted the needles, mainly to compensate for wear on the originals. I left the mains as standard, based on the fact the plugs were the right colour and looked ok.

[peter30]

I tried 132.5 supplied with ivans 'performance' kit needles, full Ti akra system. The dyno operator nearly went blind, far too rich everywhere, 132bhp peak. Eventually ended up with 122 mains, 140bhp. I'm going to go with 126 mains and some extra dyno time, should see a bit more peak power and hopefully keep the driveability it has now. I'll let you know how it goes.

[exuprob]

Thanks for the replies. Ive fitted the 132's and it feels better but my arse dyno may require a little calibration so its off to the dyno for me then!

Anyone been to Road and Track in Aylesbury recently as I think thats my nearest???

[MonkeyJim]

Anyone been to Road and Track in Aylesbury recently as I think thats my nearest???

Yes. I've used them a couple of times in the past, most recently a couple of years ago when Chris there re-jetted the R1 for the full system.

I'd happily recommend them. You might even get tea and biscuits if you are really lucky

[porter_jamie]

My 4xv coughs/jerks sometimes when you crack the throttle. a typical place this would happen would be going onto the back straight at snetterton.

i havnt bothered to stick it on the dyno yet, but i am assuming it will be worn needle jets making it go rich.

any suggestions? Dynojet do some replacement needle jets and needles. Anyone had a similar issue?