| Author | Message | ||
     Rick_a |
Does anyone know if there is enough material on the dome of a stock XB9 piston to be able to mill it some to lower the compression a bit? I need to replace some damaged 10.5:1 forged pistons and figured I may as well match the new style heads to a set of factory XB9 pistons/cylinders. | ||
| Diablobrian |
I would not remove any material from the pistons. Buell did not put any more mass than they had to into them to pass endurance tests. IMHO | ||
| Rick_a |
It's pretty easy to tell. If the underside of the piston is a flat solid mass, it'd be ok, as most domed forged pistons are made, but if the underside follows the contour of the dome it's a no-go. | ||
| Spiderman |
dunno, BUT I have some "blank" 3.5" wiesco pistons that you can cut to what you need... | ||
| Firemanjim |
Just call Brian at Rev Perf. 920 892-2109 | ||
| Rick_a |
I contacted Rev Perf. They said that they'd feel ok doing so with forged pistons but that they wouldn't take a chance on the cast pistons. I'd take you up on that Spidey, but as I'd have to pay for someone to machine 'em for me I'd be better off just buyin' the damn things proper. | ||
| Xl1200r |
If you're getting new pistons, why bother milling down factory XB9 parts? That piston is no different than any number of Sportster parts, and the head is the same as a 2004+ 1200 Sportster. You should be able to to find a lower compression piston easy. In 2004, a stock 1200 Sportster was running 9.7:1. How low did you need to go? | ||
| Rick_a |
I'm talking XB9 piston in a 1200. That's a 12:1 CR. I need it around 10.5:1-10.75. The heads are already set up for a 10.5:1 domed piston. There's already an issue with exhaust valve to piston clearances so milling the head further for a flat top is not an option. Machining for a Thunderstorm piston is an idea but I'd still have a piston dome protruding towards the valves. I was just looking for a less expensive solution. |
