Any TRX 90 big bore horor stories?

[Fast400rydr]

My daughter is ready for more power in her TRX 90 and I'm checking out my options. Seems the best is ICRacing, Hetrick, or Powroll is the bore/cam/stroke/carb areas. What I want to know is if anybody's tried something and it ended up being a total waste of $. I'm considering boring (49.5mm piston is the largest i'll go), a cam, or possibly a high comp piston and stroked. She rides trails, dunes, and flat track races occasionally. She really needs more power and speed for the track as she keeps it pinned the whole time and I'm afraid she'll blow it up.

[red rider88]

no complaints from me. check out icracing.com not sure if the sties updated yet but i thnk theres a phone number to call

[red rider88]

also hetrickracing.com

[Fast400rydr]

I've been talking to Eric at ICRacing. He is very helpful and seems eager to answer any questions I have. I just wanted to throw this out there to see if anyone tried something and wasn't satisfied with any specific combination of upgrades. Seems that if I use a reputable builder, I shouldn't have any probs. Thanks for the reply.

[212racing]

1-800-414-2973

icracing

very fast!!

[MOD 50cc DAD]

Don't forget www.robbsracingengines.com!!

[michmike420]

my daughter rides a trx 90 in the atva national series(currently 6th in points.we had 5 consecutive engine failures using parts and services from classic honda out of trler texas.we are now using a 124cc big bore stroker engine built by McVay racing724-622-3514.give charlie McVay a call his engines are bulletproof.

[Fast400rydr]

Is that Tyler, Texas and does he have a web site? I'm not too far from there, well a few hours, but he sounds like something I'd like to check out. Thanks.

[212racing]

charlie mcvay lives in pa.

[red rider88]

ya mcvay lives in pa. his website aint up yet i dont thnk

[mcvay20]

website is up with phone#'s and email-having problems with our internet provider-just call or e-mail for now. thanks!

[unclebuck]

I stumbled onto the Powroll site when I was looking for a little more power in the Grandkid's trx90. I went with the 49.5 mm 9.5 to 1 compression piston, cam and exhaust. I did a little work to match the manifold to the carb and head as well as smoothing out the intake and exhaust sides of the head. Everything went as planned and The little man is all smiles. I made a couple of calls to the Powroll people with questions about ring identification and carb jetting and they were knoweldgable and willing to spend the time to set me straight. They claim a 40% increase in power with this and although that sounds like an overblown sales pitch, my seat of the pants evaluation tells me they might be right. Don't know how it stacks up against some of the other packages out there but I am very pleased with the results of the package. Maybe the one thing to consider is that their pipe/supertrap exhaust system is a little dated in it's appearance and has a somewhat annoying drone sound to it.

[cool_racer67]

i just heard about 3 today about the powroll stroker, broke the rod, another guy looks at it and he says hes supprised it held together as long as it did (2 races)

[Fast400rydr]

Which stoker kit is that? One of the Stroker kits they sell uses that 49.5mm piston UncleBuck is talking about. I wonder how just the piston is, I mean, that seems like a lot of boring on a stock cylinder to me. Maybe I'm just too conservative. Let me know if you find out anything about the piston or if just the rod is junk, if you don't mind. Thanks, that's what I'm looking for.

[mcvay20]

The stock bore is 47mm and the stock stroke is 49.5 on the trx90. The powroll kit your talking about is a 49.5 piston kit and you can upgrade that kit to a 50mm on the stock cylinder.I've done many of them and there is room to bore them that big.
There stoker kit is a 4.5 stroke added to the stock 49.5 makes the stroke a 54mm over all.
Without the stoker kit your at a 95cc and with the stroker a 104cc. I can stroke them up a 56mm with some engine mods.I hope this info will be some help to you.
Charlie McVay
mcvayracing.com