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View Full Version : How much will it take to get an 85 250R to go 50 in 300ft of sand?



phatcat600
08-12-2004, 12:16 AM
My friends banshee goes 55 in 300 ft and I would like to be able to hang with him...but I expect 55 isnt possible on a stock bore 250.

What do stock R's pull?

Is it possible to get enough power out of a stock bore 250? How much power would it take? 250R's are only 290 pounds so it doesnt seem like it would take near as much.

What would I need to go 50?

Again, I dont wanna do anything to my cylinder.

atc krazy
08-12-2004, 12:32 AM
i think there is a 310 kit it will help alot maby a new pipe dile jet and a k&n air filter and lose the air box

phatcat600
08-12-2004, 12:42 AM
I dont want a 310 kit to expensive.

I still want this thing to be good as a daily driver and for trails, I think an airbox is pretty necessary...

phatcat600
08-12-2004, 12:45 AM
So far Im thinking CR250 head gasket, CR250 Carb, ESR pipe(?), Boyensen Dual Stage Reeds...would a higher compression piston do me much good?

I dont know how much this stuff would help really, I pretty much wanna get the most out of the stock 246 bore/stroke I can.

smokinwrench
08-12-2004, 07:56 AM
No such thing as a high compression piston.

Run the CR head gasket, aftermarket pipe, KN filter, power reeds, bigger carb. You can get the head milled down to build more compression.

phatcat600
08-12-2004, 11:47 AM
theres not like 10.5:1?

samster143
08-12-2004, 03:13 PM
To increase compression you will need to mill the head down. If you want more horsepower, send your cylinder to a 2-stroke porting specialist. That's where you will find horsepower.

AZ250R
08-12-2004, 03:23 PM
Dump more fuel in that bad boy! :beer
Put a 38 or 39mm carb on, rejet & volla you got a "stock shee eat'R". Well you'll need an aftermarket pipe too... but hey that's not mess'n with your topend right!?!?

phatcat600
08-12-2004, 03:51 PM
How much does it typically cost to get it professionally ported? Are we talkin a couple grand here or a couple hundred?

Wickedfinger
08-12-2004, 05:00 PM
How much does it typically cost to get it professionally ported? Are we talkin a couple grand here or a couple hundred?

Around $200.

Adding a Wiseco typically won't increase your compression noticeably at all (their domes are usually a little bit more crowned but this only adds a miniscule amount of compression) but there are other benefits to it. The Wiseco pistons are usually lighter, stronger and have a more aggressive piston porting than the stock ones. Having your jug professionaly ported and matched up to the new piston is a great way to increase your power - without sacrificing reliability - just don't get too aggressive. Adding a Radvalve is also a great way to give yourself an HP or two but its real benefit is roll on power and snap. I see nobody has mentioned gearing yet so I'll toss that in too. You can gear down the front sprocket a tooth from stock on that R and increase your accelleration quite a bit. It will lower your top speed but not to below 55mph. I do have to say though - why is that 55mph speed relevent? - isn't it really about who can out accelerate and cover that short of a distance quicker?.

phatcat600
08-12-2004, 05:15 PM
Its not really important but at the drag I went to they didnt give times. It was just speed runs.

I dont wanna have a pure drag bike, I want it to be reliable. Ive decided to get an ESR 310 kit, they come ported right (i think) so I wont have to deal with shops.

So far Ive come up with
ESR ATC5 Pipe
38mm Keihn Carb Kit
ESR TRX7 Pro-X 310 Cylinder Kit
some shiny silencer w/spark arrestor

the 310 will come last for sure, since i will be buying stuff as i get money

phatcat600
08-12-2004, 05:16 PM
what else will i want, and would this stuff work good for sand drags while still bein fluly trailable?

CHAINSAW
08-12-2004, 06:24 PM
Put your money into a GOOD port n polish, a good pipe (ESR or Paul Turner), reeds, and carb. That is where your gonna get your power from. I know a guy that will lay a port job on you, to do whatever you want. This guy knows 250Rs inside and out. He ported my YZ cylinder, and 370 ESR full drag ported n piped and carbed TRXs are still a bike length behind me. 310 kits, about 6 bike lengths behind. The bigger the CC the better, but a good port job will make all the difference in the world. from what your wanting.. Just go with a good port n polish job. Start from the cheapest, work your way up.. trust me. You jump right in, and buy this big expensive kit expecting to be untouchable, well it isnt gonna happen.

pm me if you want his email address.

phatcat600
08-12-2004, 10:46 PM
Hrrmmmmmm...

smokinwrench
08-12-2004, 11:25 PM
Port, polish, pipe and carb and it should be one of the fastest stock appearing machines on the drag strip

x.system
08-13-2004, 05:30 AM
I see your from Mi and thought I would let you know there will be some dirt drags this saturday at Kalamazoo fairgrounds saturday and again on sunday at Three Rivers. I am suposed to run the lights at Kalamazoo but I'm not sure I'm going yet.

phatcat600
08-13-2004, 09:44 AM
I really wanna try it out but I think I should hold off until I get all the bugs worked out, Im havin some problems with it runnin really rich but Im startin to try different jets to work it out. Also, if its at a fairgrounds there will probably be a few more people watchin than I would be comfortable with at first.

I live probably 25 miles from Kalamazoo btw.

CHARDOG
05-04-2006, 11:04 AM
If You Shave .030 To 040 Off Of The Stock 250 Head And Go Up To A Flatslide Carb Say 38 To 39 Mm And A Good Set Of Reeds And A Pipe Should Put You In The 55 To 56 Mph Range!! Did It For Me When I Started Sand Dragging!!

ATCWRENCH
05-04-2006, 11:07 AM
good job of digging up an ancient post. if you look at the upper left hand coner of each post you will see how old each post is.:welcome:

RideRed250R
05-05-2006, 12:20 AM
when my R was stock with a pipe 395 cabr, 19cc dome and no air box it did 5.2 in 300FT which was damn good i thought,.
Adam

Fox250R
05-05-2006, 01:34 AM
Playing with the timing might help...stator mods?