TORN Round 5, Crafton, TX

[Onski326]

Well no issues this race. Just me not being as fast as I'd like. Got 2nd on the holeshot but gave that up half way through the first lap. Did 8 laps total, 90 minute race. Ended up 3rd overall. Just not real happy with the bike...yet. The lack of power out of the corners is kinda pissing me off. It was great at first because the track was wet from a recent rain. It really helps it hook not having it in the power band out of corners and is an advantage over the 4pokes. But as it dried out, it really hinders it. Yes, a 350 would help. But not in the budget...yet. So I placed an order with ESR for the high comp race dome and going to have the head milled to try and get up to 205-210 psi range. I think I'm sitting around 170-175 right now. Can't be certain because I haven't checked since the beginning of the year but it does have the pump gas dome in it. Got a new set of o-rings too. I already shaved down the trailing edge of the pick up on the flywheel to put some timing into the motor. Cleaned it up too. Can't say butt dyno can tell a difference but it seems to run cleaner. Bumped the pilot too from a 48 to a 52. Still having a hung throttle when pegged and it gets close to redline. I think that's due to me lightening the slide spring too much and it not having enough tension to snap it back down. Oh well. New dome setup for next race and I think I'm going to try jacking with the gearing too. May switch the PEP fronts for a set of TRX450's I have laying around and see if the extra stiffness helps.

[2ndmoto]

Are  you selling your bike?  could have swore I saw it on craigslist a while back

[Onski326]

I have had ambitions to trade it for a TRX450R but can't get myself to pull the trigger on it. I've looked at a few that were interested but I always seem to pull out of the deal. I kind of feel bad for them. I know I'd probably be faster on a 450 but it's not near as fun and for me to get another 250R to get to where I have this one right now, I'd have to spend twice what I could buy an older 450 for. So I just end up keeping it.  I think it's got a 350 cylinder in its future. That should cure my itch to trade it. lol

[2ndmoto]

Plus, if you ever need to rebuild a 4 stroke it will cost you big. The displacement will help pull some bottom end. Bump the compression and play with gearing in the meantime. Hopefully I'll see you at the track one of these days. Good job on the 3rd place.

Best regards
- Jason

[Jerry Hall]

Well no issues this race. Just me not being as fast as I'd like. Got 2nd on the holeshot but gave that up half way through the first lap. Did 8 laps total, 90 minute race. Ended up 3rd overall. Just not real happy with the bike...yet. The lack of power out of the corners is kinda pissing me off. It was great at first because the track was wet from a recent rain. It really helps it hook not having it in the power band out of corners and is an advantage over the 4pokes. But as it dried out, it really hinders it. Yes, a 350 would help. But not in the budget...yet. So I placed an order with ESR for the high comp race dome and going to have the head milled to try and get up to 205-210 psi range. I think I'm sitting around 170-175 right now. Can't be certain because I haven't checked since the beginning of the year but it does have the pump gas dome in it. Got a new set of o-rings too. I already shaved down the trailing edge of the pick up on the flywheel to put some timing into the motor. Cleaned it up too. Can't say butt dyno can tell a difference but it seems to run cleaner. Bumped the pilot too from a 48 to a 52. Still having a hung throttle when pegged and it gets close to redline. I think that's due to me lightening the slide spring too much and it not having enough tension to snap it back down. Oh well. New dome setup for next race and I think I'm going to try jacking with the gearing too. May switch the PEP fronts for a set of TRX450's I have laying around and see if the extra stiffness helps.

What cylinder and pipe are you running?

[Onski326]

ESR 310 PV cylinder on 2nd bore, woods ported with pump gas dome, no mods to it or the head...yet. And a CT Mid pipe.

[Tbone07]

ESR 310 PV cylinder on 2nd bore, woods ported with pump gas dome, no mods to it or the head...yet. And a CT Mid pipe.

Higher compression and some race gas should help give you a little extra snap out of the corners

[Onski326]

I did get a race dome from ESR. My stock pump gas dome was at 175psi. The race gas dome got it up to 190psi and I did notice a good bit more grunt down low so far but I'd really like to bump it up another 15psi to the 205 area but I cannot find anyone to tell me home much I need to tell my machine shop to take off to get it there. I swear I read somewhere that 0.015" needs to come off to get it there but I could be mistaken. I just don't want to ruin a good head and dome with a guess. I've tried contacting ESR to see if they have a dome that's got a little less cc volume in the head but I have not heard back from them yet. Sidenote, the 190psi runs real good with no knock on a 50/50 mix of AV gas and 93 octane.

[dem3500]

You don't wamt to mill down a dome style head. The right way to do it is with a dome change. If the race dome you have now doesn't do it for you then you need to have custom dome cut

[dem3500]

IMHO your asking for trouble not running race gas with a race gas dome

[Onski326]

Oh no. I fully plan on running Sunoco 110 when I get it up over 200. I just had some 50/50 mix left over in the tank and tried it out on the 190psi dome before draining the whole thing. I've always thought 185 was the cutoff for pump gas so I figured the mix should work ok at 190. I'm almost positive it wouldn't at 205 and I'm not really wanting to experiment either to find out. lol

[dem3500]

Yea I know all about detonation! Haha

[2ndmoto]

I heard email is the best way to contact ESR. Arlan at LED has been working with ESR on cylinder and head design. He might be another source for you on a dome.


Best regards
- Jason