I have a brand new 06 roadstar midnightstar 1700 and am getting ready to install a new exhaust system. I am going to put a set of the Hard Krome Big Shots on it. I have a new K&N air filter and a yamaha jet kit to put in it as well. A friend of mine told me that the Yamaha jet kits were not that good. I bought all this when I bought the bike at the dealership last week. I have used the Cobra jet kits before and never had a problem and of course the parts man at the dealership said that the yamaha jet kit is what they install there. Does anyone have any feedback on these kits, and also what size jet would you recommend using on this set up. I live in Alabama so its not a very high altitude. Thanks for any help.

Welcome brian

I would guess that the Yamaha jet kit uses Mikuni jets since the stock jet in the bike is a mikuni. But that's just my guess. If you would give us the numbers stamped on the jets we could be sure.

Best I can tell it has a 160, 165, 170, 175 jet in it. The part number for this kit is SPD-4WM09-49-10 Roadstar carb. kit. Hope this helps and thanks for the quick reply.

brianseay wrote:
Best I can tell it has a 160, 165, 170, 175 jet in it. The part number for this kit is SPD-4WM09-49-10 Roadstar carb. kit. Hope this helps and thanks for the quick reply.

The part # helped a lot. Those are mikuni jets. I'm not sure why your friend would think bad of the kit as Mikuni jets are top notch. Another question - You said you have a K&N filter. Is this just the filter element that fits in the stock airbox? If it is you don't need to and probably shouldn't rejet. You don't need to jet with just pipes and the K&N filter. You might at most have to tweak the PMS.

Welcome to the Clinic Brian,
Yamaha doesnt make a jet kit. The kit they use varies .When I bought mine the dealer installed a factory pro kit when I got my pipes which at the time were HK 3"big straights. The kit that a dealer uses is going to vary. I live 70 miles north of atlanta elevation 1050 .I ran mine 175 and washer clip on the 3rd groove and tweak the pms to fine tune it.Hope that helps ......Coug

I am only changing the air filter itself, I will be using the stock air box. Thanks for all the help. As far as yamaha making a jet kit, all I know is it has yamaha stamped on the package and the parts man said it was a yamaha jet kit. He had a yamaha jet kit and the cobra jet kit and showed me both of them. I changed the exhaust out today and the bike runs fine. I can roll on the throttle hard and it has no hesitation or back firing. I have not been able to ride the bike as of yet so not really sure how it would react on the road with the stock carb. Hopefully I will get lucky and not have to re-jet it. Again thanks for all the input and for any further info anyone can give.<br><br>Post edited by: brianseay, at: 2007/02/12 19:55

Just unhook your AIS system if you get any backfiring with the free-flowing aftermarket pipes. I would not go into the carb unless absolutely necessary. (You might have to adjust the PMS screw at the very most. I Haven't touched mine.)
I am running a stock setup with Stage 3 (gutted stock pipes) and AIS removed. I haven't even touched the carb.
I'm at 4,000 ft altitude, and the bike runs great all over Alberta, even at lower altitude to the east.

After riding the bike today just with the K&amp;N filter with stock air box and new Exhaust in place the bike ran excellent. Great throttle response, no dead spots, idles real good. It has no backfiring during decel. I think it is going to be just fine as is. It got a great sounding lope to it now. Have not made in carb. adjustments at all. I think I am going to run it for awhile and see if any further attention is needed. Thanks for all the input.

You are correct Brian Yamaha does sell a jet kit with mikuni parts.This site should help you out....http://mikuni.com/fs-tuning_guide.html again good luck.......Coug

I have an 05 R* and I had the dealer install a Hypercharger when I bought it. They never could get it right after three trips to the dealership they still didn't have it right. Day 364 of my warrenty I bought the BAK because it ran like crap. I said to hell with their $75 an hr and did the BAK install myself. I found the carb half way out of the intake the carb heater wire off and flopping in the wind. When I opened the carb it had the 172.5 main which is the stock jet. I put the BAK on and left the main in like BAK called for but set the needle clip in the 4th grove instead of 5th like BAK called for. Still wasn't right but was a lot closer. I tried the 170 main didn't work put the 172.2 back in and set the clip on the needle 5th grove like BAK said. It runs great now. I have HKK2 pipes with home made glasspac baffles, BAK, ported stock manifold and Barons PMS. The advice IS... Leave the 172.5 main in adjust the PMS and don't mess with anything else unless you want to try moving the clip on the needle. If you don't have many miles on it just ride the crap out of it and things will settle in. Me I love to tinker I am a ex jet engine mechanic turned coputer jocky.