port job

[CR3999]

I am waiting for the 04 CR250 to get to my shop so I can buy one. I know they are low on power since they changed engine designs. I just like the honda CRs. Can your port job make it run like my old 99 did? I have a 01 now and it has seen its better days. Will I have to use race gas after the port job to make it run right or stop it from pinging?The hondas always had the rocket motor, can you make it rip again? Long live the two stroke!

 

[marcusgunby]

I dont beleive the Cr is low on power-a bit smoother on low end maybe but it was almost the hp king in 03.

 

[baggio]

Why not wait until you ride it yourself and aclimate yourself to the power delivery before deciding that it is inferior. Besides, where do you get the impression that the 04 is low on power?

 

[Faded]

Spend the time to jet it for your fuel/mixture/climate/altitude first. Ride it like this and then decide if you need the powerband manipulated to better suit you. Don't listen to the mags that slam the Honda in the motor department, there is plenty there to be had.

If you do decide you want/need the porting then you can specify fuel type (race or pump) and where you want more power (bottom, mid, top or everywhere). Be warned that the full power potential of the porting is dependent on your jetting skills.

 

[whitesands26]

The CR is NOT low on power......2002, 2003, and 2004 CR's make great power if not more than every other two stroke with the exception of the KTM...

The confusion sets in with the idiotic magazine editors...The CR makes it's hard pulling power in the mid to top end...The mag editors usually are usually novice level motocrossers...Old novice level motocrossers with a weight problem...They prefer bikes that come on the pipe easy that have good low end and can be more forgiving of mistakes..Like if you enter a corner in the wrong gear or you're going too slow, a bike with lots of low end is easy to get on the pipe and can have you charging out with the engine singing.

The CR doesn't forgive mistakes or slowness unless you're very aggressive...It's a very fast bike but makes its hard pulling power higher in the rpm range than some of the other bikes...

It's advantages are just the opposite of the other bikes...Where the other bikes tend to go flat and drop power at high revs, the CR is still pulling...HARD...A stock CR is at an advantage on long tracks verses a YZ is more potent on tighter tracks and is more user friendly.

I've ridden Eric Gorrs modified CR's and they are potent...Very potent...A stock CR 250 is fast...After Eric Gorr modifications you just have more of everything.

 

[mxer842]

i've never quite understand what a port job did , can someone explain exactly what gets done?

 

[Rich Rohrich]

Originally posted by mxer842
i've never quite understand what a port job did , can someone explain exactly what gets done?

http://www.ericgorr.com/twostktech/egportweb.html

 

[Rcannon]

Rich, remember how the "old" enduro bike ran during the 70's? I remember the Kawasaki rotary valve engines as having power from the instant the throttle was slightly opened. Not much speed or hit, but the bikes were simple to ride.

Would it be possible for someone like Eric to port a newer bike to run that way? Obviously it would mean giving up huge amounts of top end, but no big deal.

 

[Rich Rohrich]

Originally posted by Rcannon

Would it be possible for someone like Eric to port a newer bike to run that way? Obviously it would mean giving up huge amounts of top end, but no big deal.

Sure that's doable. In fact that's the type of power a lot of the vet racers ask for. Smooth seamless power that doesn't break the tire loose all the time. It's what makes big bore engines so much fun. :yeehaw: