Anyone know what RPM the hetrick pipe makes it's HP at? I emailed them and asked, but they never replied.

 

We noticed a change all the way around. I would call them instead. They are gone this week so maybe it will take a while for a e-mail reply. I talked to Robin there today so you might try to call tommorow.

 

hopefully this link will work. it has the info you asked for.

dyno on pipes

 

Thanks for the link. That was actually from a 50, but there was some interesting reading on there. I still can't figure out why a tach is not one of the first things installed when trying to tune these mini's. Even the articles didn't mention putting a tach on it. Although it did say the right way to dial them in is by HP @ peak RPM. Maybe most are not that serious about dailing them right in?

 

Peak HP rpm depends on porting and how much air/fuel you can get in the engine. With a bigger carb like the 20mm instead of stock, peak HP will move to higher RPM. With a ported cyl it will go higher still. The dyno sheet is a bit misleading too cause those are old #s and it would make you think the technigas pipe was the most powerful but they do not work very well as the whole article stated.