PDA

View Full Version : 250r


BigDave
07-16-2003, 12:51 PM
My buddy has a air cooled 250r with a 13t and a 38t. 18inch tires. Not sure of internals, but he has a headpipe and silencer. Will this bike run 80+ like he swears. Im willing to bet him money He wont break 80. It has been bored .60 over if that is much for a 250r.
powerslider
07-16-2003, 12:53 PM
No!!!
BigDave
07-16-2003, 01:50 PM
with that gearing. He would rev to an ungodly amount. Is it safe to bet him a cool $100?
250rmike
07-21-2003, 07:35 AM
umm thats a 3 wheeler so it weighs alot less so i dont know but i doubt it unless he is big bore
killer03_300ex
07-21-2003, 01:08 PM
no clue
AtvMxRider
07-21-2003, 01:14 PM
Originally posted by powerslider
No!!!
250rpilot
07-21-2003, 01:24 PM
with 18 inch rear tires he wont break the 65 mark. i run 22 inch holeshot xct, mid to top pipe, cool head, reeds, and my trailtech says 63 mph top speed. with 20 inch rear tires i get another mph or two, because it can rev higher, (they are 4 ply and alot lighter)

mine is an 87 liquid cooled quad, so naturally it is a bit heavier.
250rmike
07-21-2003, 03:56 PM
ohh never mind for some reason i didnt see that there were 18's on the back no way in he!!
wilkin250r
07-21-2003, 04:05 PM
I tried looking up the final drive ratio's of the 250r engine, and based on tire diameter and sprocket sizes, came up with 3000 rpms for 80 mph. Now I know that isn't right, but the calculations came up the same every time. Anybody else try doing this, or am I the only nerd. Can you show me your calculations?
250rmike
07-22-2003, 07:53 AM
but see this is a old 3 wheeler motor(whether its in a 3 wheeler or someone was really dumb and put it in a quad i dont know) they had less power and its gearing on 18's it would never hit 80 unless it was not air cooled and it had a really big bore on it
seven
07-22-2003, 07:57 AM
I bet if he geared it right he could hit 80+. It has little to do with power. It may take him a while to get there but it can be done. I would say put a length on how far before he hits 80.
250rmike
07-22-2003, 08:04 AM
yeah with gearing you could. little to do with power? everything to do with power getting to high speed. you can only go as fast as you engine can push you and stoo much gearing will slow you down
250rpilot
07-22-2003, 11:40 AM
when you tried to calculate the top speed, did you forget to account the front and rear sprocket in your equation??