Hi, I finished fitting all the bits on the bike last night, but will only be able to do a test run this afternoon. So, now my R1 has got a MICRON carbon slip-on, K&N airfilter and the Stage 1 Dynojet kit. Sounds ... awesome - will see how it goes this afternoon. I balanced and set the carbs up as per the instructions - DJ138 mainjet, needles on 3rd groove with stock spacers and the mixture 1 & 1/2 out. Two questions :

What is the effective of moving the needle up or down. Logic says more flow when up, but how would I know without a dyno ? Mixture screw in or out ? Which ways is leaner ?

Has anybody got a comparable setup and found different settings to work better than those in the instructions ?

The MICRON looks and sounds awesome !! Serpent headers next .....

What everyone seems to be forgetting is the main reason for jettig is not performance but to keep the bike from running to lean and burning up the valves. I know running lean will effect performance.

Originally posted by maxprimal
true twisted lean is bad
but the micron slip on in my opinion , on this bike doesnt seem to run lean in the range where rejetting is needed . it doesnt show the symptoms of running too lean , just a few turns on the idle mix screws sometimes is enuf .
some slip ons , on some bikes , do require rejetting , i've had to do it on other bikes.

Very true but some of our brothers and sisters don't know what running lean is like,so I would rather them be aware of the possiblity of not jetting. I did not have to jet my bike either M4 slip on. Better safe than sorry;)

Hi, so after I did all that, I took it for a test run and .... I've lost about 5 km/h on top-end !! Bike pulls great through the midrange, but it feels like it hits a wall before the red line !!

Any ideas ?

What size main jet comes with the Ivan's jet kit ? Stock the bike had 130 and now with the Dynojet I use 138.

There is your problem…
I just install the Ivan’s jet kit on by bike. But I have a Full Akrapovic exhaust. The Ivan’s kit comes w/132.5 main jets, recommended for a full exhaust. For a slip-on exhaust you should use the stock 130 main jet. This is what Ivan’s recommends.
If you are using a 138 main jets you are definitely running to rich. ;)

Is jetting needed on a 99 R1 with full mig system. Should I get a K&N filter, will this help or hurt. I heard jetting isn't really needed on these bikes. When should u jet?:blah

Hi, I'm about to change the carb setup and will post the results.

What is the effect of raising or lowering the needles ?

:hellobye
i work as a dyno technician and you are all right and wrong, you need to have any jetting set up on the dyno and gas meter's without this you are guessing and the instructions given on the box are just guide lines, micron are the worst pipe along with art, redline.two brothers, quill. the best pipe is a full ack as they have time after time proven on all the bike's we fit them to.

So as to the question what jets let some else have the job if they have the gear, we charge a flat rate on all setup's so if it takes two hours or ten hour's then one fee is payable.

keep an eye on my big bang r1 it's gonna be awesome.


need any technical advice email me
rick007