pipe information

[nastynotchback1]

How do yall get clutch first when a pipe change can throw all you clutch work out the window?

[EthansDad]

on the 2010 50cc, I assume you are running the 90 pipe option on a stock cylinder. that is a really good combo and likely won't get much better than that on stock cylinder. that combo makes great top end power, but very very little down low and tends to bog down low on the 21mm carb. I don't run XC, but if I did with our 2010 50, I'd run that combo and drop to a 19 or 20mm carb. I might also try switching to the 50cc pipe (which brings more bottom-mid power back) for XC racing. when the 50s get real "pipey" or peaked out on power, they also tend to burn up clutches, not good for XC. another reason I'd experiment with the stock 50 pipe - easier on clutch life.

on the 70, someone else already said this, but you can't do upgrades in stages from stock to full tilt and have your investments come with you. say you take a stock bike and put $500 in it (pipe, mid grade cylinder) then are ready for more power. you'll need to go to higher end cylinder, which will involve you switching out the cranks, changing pipes, and changing ignition. a lot of throw away stuff from the stage 1 upgrade.

out of all the other things you listed for your 70, I'd buy the PVL first. that WILL carry with you to your next upgrade and give you a bit more go juice now. if you go away from that stage 6 top end, you will likely need to get into the crank to switch out bottom end for some higher $$, but that is your next step.

on the high dollar cylinders, you really don't need to port them unless you plan on trying to run top of pack at a national. they come pretty darn close as they are. you might want to spend the $ though to have the cases blueprinted and make sure someone that knows what they are doing can set up your squish and proper cylinder install to get the most out of it.

-EA

[kfx450]

See this is great information with out the bashing.

Suspension stock 41 a-arms and axle.
4-1 offset front wheels for less bumb steer and as good or better handling. Stick style dampner. HLS shocks (agree suspension is the first thing that went on our 09 bike.) Most of you don't know about these shocks and my mini shock comparision is very litle but these things soak up everything we have thrown at them and work very well with a 50lb rider. I have seen them soak up doubles when my sone came up so short that the bike stopped on the landing but he never came off of the bike or complaind about hurting. sorry for the rant just like the shocks. We are currently running out of motor but the suspension seems not to be the week link at this time. I know after the 70 motor we may have to go back and change it.

We like torque for the hills and tight turns. But on our current bike (Stage 6 50 with stock apex pipe) have got around it by running a higher rpm.

As for building a motor around a pipe, That is not what I am trying to accomplish I am just trying to find the right pipe for the application or one that is close that I might be able to use on the next application. The PCS and the hetrick gen III are what I am looking at currently, But has anyone tried the new Mach I pipes designed for the 70, or has one used the Faster than mach I pipe. I know the owner of the company is no longer on here but does the pipe work?

The 09 will become the seventy and it has around 30 races and 5-10 hours a week ride time for 2 years so I am planning on changing out cranks with this build. I am currently planning on putting in an 85mm rod and a spacer plate. that way when you go to the next step it is already done. I have also been told this will give us a litle more bottom.

PVL will be the next step as it is a great investment from what I have seen on the 86cc bike that I have been working on.

[EthansDad]

those are all good pipes, but again I don't think you'll get the most bang for your buck with those running a stage 6 top end.

Check with the dealer, or maybe someone has the numbers here, but what you need to know for each of those pipes is the RPM at which they make max power. I want to say on most of those you listed, its in the 13k range (someone correct me if you know better). the question you then need to ask yourself, will my top end, crank and ignition get me to the peak RPMs I need to take advantage of my high dollar pipe? likely not. will the pipes make things better with your current setup? probably, but then again, so would the pipes you currently have at half the cost.

don't mind my opinions on this stuff, I'm just a cheap skate when it comes to upgrades. I don't mind spending the money, I just want to make sure I get what I pay for, and don't over buy because my A.DD. kicks in and compels me to buy something "new and shinny".

[kfx450]

that is what I am trying to do. I have a gen II hetrick pipe from a parts bike. I am willing to try it first. I may put this motor together and only last a couple of months and we will be putting together something more top end. and then again we may put this together with an older pipe and run it all year. Just trying to get all of the information that is out there and maybe get something said on this post that will help others with the same questions.

I am not afraid to think outside the box. we are going to start with the stage 6 street racer kit. It is a steel cylinder that has very similar port timing to the stage 6 sport cylinder but more torque and a litle less top end. but at half the price how do you not try it first. The only thing after getting it is I would like to see a single ring piston for just a litle more performance. Also I will check the squish on the cylinder this week and may have it milled a litle as this cylinder is flat across so it will be very easy to do.

jayme