[Q168]

Hello all,

I am in Utah and most of my riding is between 7000-10000 feet. I recently added an HMF Swamp Series pipe, but I am fighting with getting everything tuned properly. Going from what HMF customer service told me, they didn't have much research into this kind of elevation, but recommended that I leave the 162 main jet in the carb as opposed to their 165. It is running great at WOT, but I am getting a small backfire every now and then when I am using the engine's compression to come back down the mountainside. I currently have the pilot set at 2 5/8 out from being seated in the carb. I checked the plug and it looks good, but I would love to eliminate those small annoying backfires when coming off a slope. Has anyone here that rides at this altitude have the same or similar air filter/ pipe set up that I do and has been able to find that "sweet spot' on the pilot screw? Thanks in advance.

 

[rich450es]

welcome to the forum from tooele UT !!!!!!
where ya from man ? ....i would try turning the pilot screw out 1/2 and drop the clip on the needle 1 notch ....

 

[Q168]

welcome to the forum from tooele UT !!!!!!
where ya from man ? ....i would try turning the pilot screw out 1/2 and drop the clip on the needle 1 notch ....

Thanks for the warm welcome rich450es. I am from Kamas, so the Uintas are right in my back yard. I have adjusted from 2 - 3 turns in about 1/8 increments and test every time with very similar results. As I said, it runs beautifully with the exception of that one little issue. Maybe I'm trying to be too much of a perfectionist. The needle on my machine doesn't have any additional notches, so I can't do much. I know that it came with a 162 main, which is supposed to be for up to 6000' if memory serves. I am wondering if I should bump up to the 165 in the HMF jet kit since I am getting so much air with the K&N and HMF pipe. Thoughts anyone? I still feel like I am running lean.