Author: Bad Boy Bobbers & Customs   Date Posted:19 January 2018 


This is a subject we get asked about a lot so we thought we would share our experience with re-jetting these bikes for aftermarket Exhaust Systems & Air Intakes. We sell a lot of Vance & Hines Short Shots as there aren't a huge range of exhausts out there & the Vance & Hines Short Shots do sound awesome. Only a trained ear could pick them over a HD when nailing it from the traffic lights. Just like you we figure, why reinvent the wheel, there are plenty of Jet Kits on the market & instructions for setting the Carbies up correctly. It will be easy they said....well its not but we do have some tips that might help. Firstly Jet Kits, we looked at all the various XVS650 Jet Kits we could find & it was frustrating. Some kits had Main Jets but no Pilot Jets, Others had Adjustable Fuel Needles but no Main Jets. We decided we could do better. It was quite a task as we had to turn to Japanese manufacturers to produce our own Adjustable Fuel Needles which took quite some time. In the meantime we assembled a range of quality Mikuni Main Jets & Pilot Jets. We also noticed how soft the OE Float Bowl Screws were & how easy they are to strip so we sourced Stainless Steel Cap Head Screws for our Jet Kits so you can replace the factory screws. So now we have a comprehensive jet & needle kit so which ones do we use? There are many suggestions on the internet on how to correctly jet a XVS650 but as is typical with Internet Info, its hard to find a consensus. We fitted an XVS650 Custom with V&H Short Shots & a Kuryakyn Hyper Charger. The Hyper Charger does include a Jet Kit & instructions to use 122.5 Main Jet & 35 Pilot Jet which is large jet. Now no offense meant to Kuryakyn but with this jet combination the bike ran like a pig, it was unrideable. We looked at other suggestions & in the end used the tried & tested trial & error method. I wont bore you with all the details but the combination we used came from within our own jet kit and the bike has been running great & making good power ever since. So our recommendation (& thats all it can be as your bike may be different or your air thicker or thinner than ours or some such unknown variation) for Kuryakyn Hyper Hyper Charger & Vance & Hines Short Shots is: Stock Pilot Jets, Size 100 Main Jets, Diaphragm set on 4th Slot & Fuel/Air Mixture Screw 2.5 turns out (gently screw in until screw seats & then turn out 2.5 turns). The bike sounded good on the bench with no hesitating or popping on acceleration but until the engine is under load, you never really know. One road test & we knew we had nailed it & didn't change a single thing. We recently placed a substantial order from Japan on our Jet Kit Components & this has enabled us to reduce our price to you from $140 to just $99. If you are in Australia, then there is no better value or more comprehensive kit on the market. Good luck with tuning your bike, we hope our experience saves you some hassle & gets your bike running great so you can hit the road.

Bad Boy Bobbers & Customs.

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