| Author | Message | ||
     Buellblastrider |
hi all. new to this part of the site. im a certified harley buell technician with a xb12s myself. unfortunately i have never worked in a shop that carries the Buell franchise so only experience i have with them is my own with my bike. So heres my question. I have a buddy who is also a certified harley/buell tech, he has a 2003 1200 sportster and wants to throw some buell parts in it. I know the tube frame heads are popular on sportsters but not sure what else is needed/ recommended. any advice would be appreciatted and with part #'s would be great too. | ||
| Blake |
XB heads are preferable, with which XB9 pistons are an inexpensive upgrade for increased compression. | ||
| Buellblastrider |
ok thanks for the info. i wasnt sure if xb heads would be ok or not. do xb's have piston jets? if so will the sportster not having any be a problem? with xb9 pistons im sure he will need to do some adjustment to his fuel delivery correct? obviously being carbed it wont be a big deal but should he just rejet it or look at a bigger cv carb? (carb debate i know is big, everyone has their preference.) thanks for all the advice | ||
| Blake |
Rejetting should work fine below 100 RWHP. If you want more power, you'll likely need a bigger carb. The XB9 pistons bump compression ratio up to 11.5:1. He'd be wise to bump the fuel up (enrich) and of course always use high test octane. Some very basic headwork would be beneficial too. Be sure to check and adjust the squish. | ||
| Blake |
The piston jets help cool the pistons for sure, but the Buell engines surrounded by the big aluminum frame and also with the OEM (EPA compliant) fueling run hotter. Good point though. The honest answer is that I don't know. I do know that Sportster folks have been using the XB9 pistons and XB heads for a very cost effective upgrade for years. There should be info out there if you google. Or give one of the performance shops listed on our sponsors page a call. They'll not steer you wrong. | ||
| Buellblastrider |
Well thank you for your honosty and thank you even more for your advice. | ||
| Jeffreyh |
"The XB9 pistons bump compression ratio up to 11.5:1." They bump it to 12:1 not 11.5. | ||
| Blake |
That is correct. Thanks for catching my goof. | ||
| Buellblastrider |
what do you think about cam choice? will stock do ok? is there any non stock cams he could run without being concernec with valve to valve or valve to piston clearance? | ||
| Blake |
What kind of performance is he looking for, top end rush or big low end, or balanced around mid-range...? | ||
| Buellblastrider |
i would imagine tq. and low end? would stock xl cams work without clearance issues or is there a "aftermarket" cam that he could benefit from without the clearance issues? i know we could do the math but i would rather hear from personal experience. sometimes whats on paper and real life arent the same | ||
| Newxb12ss |
A Sportster running pump gas won't tolerate 12-1 compression on the street. And the stock Sportster cams would cause catastrophic detonation. | ||
| Outdoors |
Why not pick up some good used thunderstorms and pistons. I have saw some nice used ones selling on ebay and they should be cheap as people migrate to the xb ones. Since the M2 ran this set up with the sportster D cams there shouldn't be any issues except normal tuning. Tuned XB heads are no doubt better at the top end but most sportsters are about torque and midrange running. At least it is another option. |
