racing a 250r

[woodsracer144]

ok, i had a 87 250r and it had a built up FTZ motor in it, she was a 265 and she flew like the wind. i had a sparks pipe for TT and it was the fastest quad i've ever rode. im looking to but another becuase i tried the 4 stroke seen and i hated it, but this time around i wanna do it right.

i run mostly woods and im thinking about doin some hairscrambles in the fall after i get some seat time. what is the best set up to run i found a R by me with a no link with a axis and 19 3/4 front shocks and +2 a-arms, there are 3/2? rims on it now and its sopose to make up what a +3 with 4/1's would be at. so could i have 4/1s and be good or would i still be a bit on the wide side?

also what moto-exhaust set ups are killer in the woods? im thinking there a pro cirut exhaust or its a paul turner...

also what CC's are good its open by me fore what ever you have the money for? how much can a 265 push out? are they able to keep with teh 450's? thanks

[LONG-ROD]

4/1 is 1 inch wider then 3/2, the is 4" outside lip and 1" inside lip. sparks pipe is awsome, so is the paul turn mid, ESR, trx, are good pipes. I have less then 265, and I was beating 450's all day at the dunes while we where draging. in the dirt the 450 has one big advantage, " traction" and when it is muddy I just spin, while they can get enough traction to pull the front end up. But the answer to your Q's is yes, you can build a 265 to beat the pants off a stock 450r

[dove]

i thought it was the other way round a 4+1 is 4inch in and 1inch out,so that would narrow the front by 2 inch compared to 3+2

[woodsracer144]

the 4 by 1's are 4 in and 1 inch out...

i just know that the 450s have atleast 50 60 hp now... i dont know what the 250 or a 265 would pump out.

[LONG-ROD]

No, 4/1 off set is wider than 3/2 off set, I beleive 4/1 is as wide off set as you can get. I also think 3/2 is stock

[fastrnrik]

4/1's are 4 in & 1 out. I suppose they could be run backwards, but I don't really know why? I couldn't imagine the dam wheel sticking out that far LOL

I have both 4/1's and 3/2's for my TT bikes. We can change the width as track conditions change.

[jcs003]

i read an article about a engine builder (MP racing) in oregon who builds a 265 that eats modified 450r s all day. but, only what i read.

[JIMFROMTEXCO]

4-1 is the narrowest rims you can get. it has a 4" in side lip and a 1" out side lip. plus 2 arms with 4:1 wheels is the ideal set up for woods. with the 4:1 wheel you get less "bump steer".

if you set the 250r up right and can actually ride, you will have no problem beating 450s in the woods. i love my 250r and will never ride anything different again. to be honest the 250 is so predictable that less technical trails are boring for me. just get a good port job pipe, and carb to fit what rpm range you like.

[rustyATV]

I raced my 250R in woods from 1999 up until 2006 and, in all honesty, I wouldn't seriously race it any more. Not from a handling/power stand point, but from a maintainability/replacability one. I recently sent off parts to my supplier and he told me that I'm the ONLY guy still working on (not racing, but just working on) a 250R. Replacing some of those parts might be tough to do.

That said, what's most important for a two stroke in the woods is broad, smooth power that comes on early. I ran a mildly ported stock cylinder bored to 265cc's with only 185psi of compression for years. It didn't quite have the power the 450's did, but I didn't have to work the clutch too much and could focus on lines. I use a Paul Turner Type 6. A friend tried to get me on the low-mid range Paul Turner 2003 Race pipe, but you need your engine set up to make up for the loss in low end power, otherwise you're going to work too hard. I don't have experience with other pipes, so I can't comment.

If I recall, stock width for an R is about 45 inches, so +1 arms with 4-1 wheels puts you at about a 46 inch wide front. I ran this and found it to work rather well.

The +2 arms with 4-1 wheels will leave you about 48 inches which is a bit wide for woods. I've heard of people running this, but it really depends on the series you run and how tight they make their tracks. For instance, a local series near me I know of people running their MX width quads with no problems, but the same setup in Mid East would get you stuck between trees.

[woodsracer144]

thanks for the imput on that! its alot of help, i know a guy that has a TON of 250r parts so i wouldnt have a hard time finding parts. when you ran the woods did you revv it way high or keep it at a mid range on the RPM? when i had my R i have mostly a open feild tail up and down hills and corners and alot of woods and like .2 miles of mx and i would have that whing WTFO all the time! and the power band always hit at the perfect times.. and some times hit harder than it should. i would be at the bottom of a hill and come out and just pinned and it would hit hard and it was just... speachless for that moment... its a feeling that i love and cant get over. i tried out the 4 stroke deal and i dont care for it. the only nice thing is im not mixing oil but its not that hard to do. if i would have to rund a 4 stroke it would be a yfz but i wanna be onboard the 250r who makes a good motor set up?

[rustyATV]

Well, keep in mind that woods races are endurance races, and a hot motor is going to wear you out. I know people like to say "A good rider can ride any motor, blah, blah, blah...." but the reality is you choose the right tool for the job, and a hard hitting, wheelie popping motor will bring you more trees than trophies. Your motor should work for you, you shouldn't have to work for it.

My quad was tuned low, really low. It came on pretty much off idle and pulled hard, but smooth in the bottom 1/3rd of the rpm range. The mid range was flat, you barely noticed you were in it, but in the upper rpm's the engine fell on it's face and didn't have much to give. Not that it wouldn't rev out, but you really had to short-shift this engine compared to most. It was still fast, but it didn't FEEL fast, and that's the key.

I had it tuned this way because the vast majority of what I raced in had me snaking around trees, rocks, and roots. This mild torquey setup let me keep the motor in gear and leave the clutch alone so I didn't tire myself working the clutch or fighting the quad. I almost sounded like I was idling around in tighter stuff, and friends following me could barely tell I was shifting gears because I'd rarely rev it out. This REALLY helped me keep traction when grip was hard to find, which was worth gold in wet races and creek crossings, where your average rider liked to ride the rev-limiter and spin their tires for some ridiculous reason; my crossings were usually drama free. Also, such a low ended motor really helped me get off the line for dead engine starts; I was usually one of the first few out of turn 1, even against some big engines.

All of that combined to make me faster overall, despite being down on power. I had a number of friends on four strokes who I was faster than (at the time) ride my quad and be totally blown away by how mellow it really was. They thought it was going to be some tough to manage beast, but it was quite the opposite. In fact, they had more power than I did.

I guess to sum it up, in the woods the 250R's asset isn't it's power , so don't worry about trying to "run with the 450's"; they can't use all their motor in the trees, anyway. Your asset is nimbleness. The 250R is about 50lbs lighter than the 450's when dressed out for racing, and your center of gravity is MUCH lower. Play to these strengths, and just worry about making your motor smooth and reliable.

[rustyATV]

Oh, and as for engine tuning, I actually had very little done to my cylinder. It was an 88 jug with flow work done to the transfers, on the underside of the cylinder. I also epoxied the two secondaries and raised them about 1/2 a degree (I think, it was a while ago and a friend told me how to do it). I also widened the exhaust slightly, but did NOT raise it.

That was it for porting. I also bored it out 0.080 over and used cool head to raise the compression to 185psi to max out on pump gas. I used an early model piston, so it was a base plate motor.

Other than that, a Paul Turner Type 6 pipe and a Keihin PWK 38mm Air Stryker carb, and '97 CR250 reed cage were all that was done.

[woodsracer144]

yeah i understand what you mean by the motors would make me tired and stuff, i know there are alot of guys out there that have 10 grand in a motor a or a full quad and theres some random kid with a crappy helmet bald tires and a stock quad smokes the piss out of him... i know its the blance of quad set up and ride ablitys, the quad i'm looking hat has a aftermarket chassie with 19 1/3? ingh axis shocks with a no link rear shock all fully adj. i did some re search on the quad and it was bob linns or lind? from MN and he race pro or pro am with it. im not sure. but theres a +2 front end with 3/2 rims. i talked with the company that made the a-arms and he said its about a 2001 built because they now changed the set ups to a +3 with 4/1's

the motor has the stock cylinder on it with what looks like one of duncans carbs on it, there is a reed spacer on the motor that about this think > < or thicker its huge, theres a cool dome and and runs on 110 race gas. teh y guy said he thougth the motor was a stoker but wasnt sure and spent clost to 8 grand on it.

[woodsracer144]

Originally posted by rustyATV
I also epoxied the two secondaries and raised them about 1/2 a degree (I think, it was a while ago and a friend told me how to do it). I also widened the exhaust slightly, but did NOT raise it.


what is the epoxied the secondaries? the "ports" on the side of the cylinder that takes the air to to top of the cylinder?

[rustyATV]

Can you get pictures posted of that quad? I'm curious about the chassis and front end. Do you know if it's an altered geometry frame? (i.e. narrow front)


Originally posted by woodsracer144
the motor has the stock cylinder on it with what looks like one of duncans carbs on it, there is a reed spacer on the motor that about this think > < or thicker its huge, theres a cool dome and and runs on 110 race gas. teh y guy said he thougth the motor was a stoker but wasnt sure and spent clost to 8 grand on it.

Hard to say what that motor is, there are tons of different setups out there. Probably it's probably ported for MX, though, which means it'll have a hit and might be a bit too soft in the low end to really be good for woods racing. You'll have to find out what you've got and talk to an engine builder.


Originally posted by woodsracer144
what is the epoxied the secondaries? the "ports" on the side of the cylinder that takes the air to to top of the cylinder?

I need to get a good picture of this because people ask me often, and I have a tough time explaining.

Basically, you have five intake ports and two (into one) exhaust ports on teh 250R cylinder. If I remember my lingo, the two intake ports on either side of the exhaust (opposite each other) are the "Primary Transfers", the next two are the "Secondary Transfers", and the single intake directly across from the exhaust is the "Boost Port". (Could be wrong)

Anyway, the Secondaries have a design flaw that causes the intake to "hook", or shoot towards the center off the cylinder. You can see evidence of them in the tops of used pistons in the form of sharp clean areas in the carbon buildup. Adding epoxy to the right spot re-drects the ports to shoot right at each other, and greatly improves bottom end power. It wasn't until I did this that my engine developed tractor-like qualities.

I'll see if I can get a good picture to illustrate.

[woodsracer144]

ok the arrow thing didnt really work the reed spacer is like > < its a good 3/4 inch at least...

i dont really under stand what your talkin about on the secondary and all that...

its a prp chassie with a no link. they didnt change anything but a 15* rake change on the front end... (i dont know what that means)

[woodsracer144]

motor

[rustyATV]

Yeah, that's a HUGE reed spacer! Biggest I've seen. Mine's only 1/2in.


Originally posted by woodsracer144
its a prp chassie with a no link. they didnt change anything but a 15* rake change on the front end... (i dont know what that means)

The rake is the angle the front of the chassis makes where suspension mounts, where the frame looks to bend upwards. I think the 250R's rake is 14 degrees, where most of the new quads have a small 5 degree rake.

Finally got a couple of decent pictures.

First is the cylinder with the epoxy in the secondaries. Notice the brownish areas that the arrows point at. This is where the ports were filled in and filed slightly so that they are aimed directly at each other. This causes the intake to sort of "bloom" in the back of the cylinder and scoop the spent charge out to the exhaust, giving you a cleaner charge for the next power cycle.

[woodsracer144]

ah i under stand it alittle better now... i've only seen on other reed spacer that big and it was on a guys ESR 330 and it was a dune quad...

[rustyATV]

This image shows where the "hook" gets its name. The piston the left (never mind the grinder marks) is from a non-epoxied cylinder. It has a couple of sharp areas (followed by the arrows) you can see in the carbon where the intake jetted in. This is the "hook", and means the flow is being concentrated and forced to the center of the cylinder when it comes in.

Meanwhile, the piston on the right is from the cylinder after it was epoxied. The red lines show the approximate locations of the secondaries. Notice how the clean areas are broad and even, without "hooks".

[woodsracer144]

holy cow! yeah thats a ton different! so do most people when they P&p do that or no?

[rustyATV]

I get the feeling it's not well known. My parts/suspension guy built 250R motors for over a decade, and even raced pro at one time, and I had to show it to him. Also I've been looking over the Duncan powervalve cylinder I'm going to put in, and it has the hooks cast in it as well.

[woodsracer144]

how much does it cost to get that done, the fileing down and all that do you dont ahve the hooks

[rustyATV]

Depends on who you get to do it. I've got it on two cylinders. One I did myself.

I had to buy titanium epoxy, a couple of flexible files, a scribe, layout fluid, and a carbide cutter and flexible drive for my dremel. I'm no porting expert, so if you look at the first picture I posted, under the left arrow you can see where the cutter jumped out of the port a couple of times. Fortunately, that wasn't where it'd cause a problem.

Between that and the cost of the putty (almost $90 for the smallest size, now), you're probably best off calling around and seeing if you can find an engine builder who knows about it.

[woodsracer144]

i dont think that FTZ i had had that done to it. there went hooks on it but it was covered with carbon all over not bare patches...

[C-LEIGH RACING]

Originally posted by rustyATV
Yeah, that's a HUGE reed spacer! Biggest I've seen. Mine's only 1/2in.



The rake is the angle the front of the chassis makes where suspension mounts, where the frame looks to bend upwards. I think the 250R's rake is 14 degrees, where most of the new quads have a small 5 degree rake.

Finally got a couple of decent pictures.

First is the cylinder with the epoxy in the secondaries. Notice the brownish areas that the arrows point at. This is where the ports were filled in and filed slightly so that they are aimed directly at each other. This causes the intake to sort of "bloom" in the back of the cylinder and scoop the spent charge out to the exhaust, giving you a cleaner charge for the next power cycle.


:eek: Hummmm, this pic has got mindcrime wrote all over it with that epoxy in the port.

Rusty, would you do something for me,,,, please call your "supplier" & tell him the ol 250R aint as dead as everybody is leading him to beleave & that he may need to wake up & check things out, because that ol boy is comming back.
Neil

[rustyATV]

Originally posted by C-LEIGH RACING
:eek: Hummmm, this pic has got mindcrime wrote all over it with that epoxy in the port.

Rusty, would you do something for me,,,, please call your "supplier" & tell him the ol 250R aint as dead as everybody is leading him to beleave & that he may need to wake up & check things out, because that ol boy is comming back.
Neil

Yeah, this was with Jeff's guidance, but by me, hence the "oops!" in the corner of the one port. My 85 cylinder that cracked is the one he did, and it looked MUCH better. Since I don't have to do any cutting and I still have a bunch of that epoxy, I'm thinking I'm going to add this to the Duncan cylinder I have.

My guy just responds to demand and, right now, I'm the 0.5% that still asks for two stroke stuff. A year or two after the 450's came out he said he noticed a surge in 250R stuff, but it's died off.

He's actually on the two stroke side. When I get him on the phone he'll occasionally start a rant about how expensive junk has gotten. He's a hoot.

[woodsracer144]

haha thats funny, i and gonna race a 250r as long as i can becuase its cheaper for me and alot easyer to work on.... and i feel they are just as fast!

[C-LEIGH RACING]

Woods,
is it just a 250 or 265 engine that your wanting or maybe a big bore or maybe not.
A nice ported high compression 310cc might just trip your trigger out in those woods & have plenty of grunt for most any course or tight spot.
I've seen some 270cc grunt engine owners with mighty big grins on their faces after riding it.
Neil

[woodsracer144]

i would take a 310 hands down and run it, the quad im lookin at has a full aftermarket chassie, a-arms and a no link swinger with axis all the way around fully adj, i was hoping that i could throw on some 4/1s on and be tight enought... im gonna be racing in D23 (its MN racing) and its gonna be hairscrambles... and i have to do one mx race to race a kid that is a die hard 4 stroke guy and calls me a *** and gay for wanting a 250r so im wanting to race and show him that a 250r can be race and do well... the race track is more a 2 stroke track anyways... but back to the quad i want... i would like a WER or a GPR steering dampener. and a nice built motor in it, i dont really care if it was a PV motor or not. but theres a OMA national race at Spring creek MX park and theres a national Hair scramble at Sugar camp that they have for the bikes its a new race thing... but i dont know that the limits are with the other races... the D23 that i would run is open. but the OMA im think is a 450 4 stroke and a 265 2 stroke...


that FTZ i had was a crazy motor and just flew with the sparks exhaust i had

i really dont know what set up to run...

whos a good low end set up? im planning on racing the motor it has untill it blows or riding it as long as i can... and then rebuilding the whole thing with a aftermarket cylinder and all that...

[C-LEIGH RACING]

Hummmm, I cant answer that one for you, not with out getting my legs switched.
Neil

[woodsracer144]

what? gettin your legs switched? thanks for all the help guy also, it means alot!

[woodsracer144]

Originally posted by rustyATV
This image shows where the "hook" gets its name. The piston the left (never mind the grinder marks) is from a non-epoxied cylinder. It has a couple of sharp areas (followed by the arrows) you can see in the carbon where the intake jetted in. This is the "hook", and means the flow is being concentrated and forced to the center of the cylinder when it comes in.

Meanwhile, the piston on the right is from the cylinder after it was epoxied. The red lines show the approximate locations of the secondaries. Notice how the clean areas are broad and even, without "hooks".


i've been lookin at those pics for a really long time... the one with out the hooks, what side is the intake and exhaust?

[rustyATV]

Originally posted by woodsracer144
i've been lookin at those pics for a really long time... the one with out the hooks, what side is the intake and exhaust?

Both pistons are oriented the same way. The one on the right is an early style piston, the left a late style one. Only reason I switched was because my supplier kept the late ones in stock.

[woodsracer144]

so then the only differance is the picson skirts on them? i saw theres a hole in the on on the left and not on the right... what would that do for you if you had it bigger or smaller?

[rustyATV]

Aside from the 5mm lower wrist pin, yes, the only difference between the early and late pistons is the shape of the intake.

I think that the early piston flows better, but when Honda went with the "bridged" intake in '87, they didn't have a wide open path to the crank case, so they went with the "window" design to further improve piston life. I'm guessing, anyway..

[woodsracer144]

so would a larger "window" in the piston skirt help get more Hp?

[rustyATV]

I can't really speak to that; I've never modified pistons.

That said, Loren Duncan told me to drill a hole high in the intake side of the early style piston to make more power. Check it out in this Duncan image.

http://img.photobucket.com/albums/v11/hoppy/big-hondatrx250r-2.jpg

I'm a bit of a Duncan skeptic, though.

[woodsracer144]

when you say "I'm a bit of a Duncan skeptic, though" what do you mean by that... not a big fan of them?

on motors with Pv's i've hear that JRD and duncan are the better of the makes and that ESR isnt as well as them...

does CT make one?

what steh advantage with a aftermarket cylinder then a stock one?

[C-LEIGH RACING]

Years ago, the concept of placing a hole in the side of a piston on the intake side at the top, was to promote cooling flow onto the underside of the crown & to lube the top end bearing.

That Duncan cylinder kit for the TRX250R has always looked good, like as if all the other cylinders on the market were look at & then refinement were done improving the Duncan one.
Only thing, the Duncan PV cylinder was produced before the others. You should have seen some of the early models, stock cylinders welded all up where the pv was at.
You got to give it to Duncan, they worked at it hard testing as they went to produce their cylinder.
I've heard some say the ports were just crap in the Duncan cylinder, but hey, aint that what porting people are for, to make it better.

For the TRX250R engine, in aftermarket cylinders offered, you have the Duncan one in the pic, the Pro-x from LA Sleeve & CT Racing, the new Eddie Sanders Racing cylinder kit, & there was a cylinder kit from PSI.
CPI has cylinder kits for the 250R, but cater more to the drag type of racing.
You can get an aftermarket cylinder kit from a 250cc up to a 500cc & all have refinement to their design that are far past what the stock Honda cylinder can offer.
The PSI cylinder kit, was probably one of the most finely machined pieces of work & best looking on the market, but due to some problems, was mighty hard to finish a race with one. The problems encountered I think came from the adjustable head dome & the adjustable on the go big air carb.
Most everytime you seen a rider adjusting the carb, in about a lap they would be sitting beside the track seized up.
Its some members on here have those PSI cylinders & have worked with them to get them to run very well.
Neil

[woodsracer144]

wow thats crazy... are all them places still making them? i know CT is and Duncan... who would you rank of of the better ones?

[rustyATV]

They're all still selling them. The Duncan is going to set you back the most, $1800 for a new cylinder only (like in the picture), and something like $2800 for a complete kit (pipe, reed, carb, etc).


Originally posted by woodsracer144
when you say "I'm a bit of a Duncan skeptic, though" what do you mean by that... not a big fan of them?

I got Loren on the phone a little bit back and some things he was trying to tell me about fuels was making me chuckle more than enlighten me, such as "Lowering compression will not lower octane requirements", and some other things.

[woodsracer144]

oh i know just what your talkin about! theres a guy at a shop by me that thinks theres no diffrance in a 250r chassie through out the years... 1 easy change is the vin location, 2 the pegs were changed...

i also had a motor and a hood and a chassie from a sled and asked him how much they would give me for it and they said like 5 bucks... and i told him to go F him self becuase a week before i called and aske about how much a motor would cost and he said 650 and 125 for the hood and 150 for the chassie...

its a big **** over there... and i dont go there anymore... its all off line...


so do you think them CT kits are a fair price?

or how much is a built r motor from a part out or something?

[woodsracer144]

how much would a ESR 265 PV be worth.. it needs a new piston? the piston started to melt... thanks

[turdboy]

Hey I remember that 250R. It was Bob Linds and he was fast on it. It used to have a duncan PV motor. Bob now races bikes. How much did you get the quad for?

[woodsracer144]

as fas as a price i'll tell you in a few weeks...

[jon370r]

My set up this year.

[woodsracer144]

what are you running tor a cylinder

[05LSR250R]

Might be a Rotax top end............

[C-LEIGH RACING]

Reguardless of what the top end is, much as he has spent getting that R looking like that, if it was mine you could rest assured it wouldnt be sitting on no melting ice, BUT, they sure do stay clean running on it.
Neil

[2-330s]

woods if you want a good grunt motor call arlen at l.e.d. performance. his motors might not post the biggest hp numbers. but he makes a nice long power band that is usable. you might want to try a weighted fly wheel also. smooths the hit out a little.

[woodsracer144]

hey 2-330's. you dont happen to have any big bores at your place yet? i saw you sold 2 of them on ebay a while back...

[jon370r]

Originally posted by woodsracer144
what are you running tor a cylinder


Yes it's a Rotax RAVE valve cylinder that I grafted onto the 250R base. Ive been running it for almost 2 years and am very happy with the broad power band range. I would guess that its at 60 h.p. or alittle more on pump gas and very rider friendly. I ran it almost wide open in 5th - 6th gear for the 30 miles between Glamis and Gorgons wells and back (60 miles round trip). I went from Ice racing in Maine to the southern cali. dune and never rejetted because it was running so well I didn't bother. Last weekend I rejetted for the first time in 1 1/2 years because I didn't want to blow it up at the ice races.

[2-330s]

hey 2-330's. you dont happen to have any big bores at your place yet? i saw you sold 2 of them on ebay a while back... none for sale. i still have a 330 sparks for a spare and will be running my ftz for the rest of ice racing. can't wait to let it run on the half mile this summer!

[86250rrider]

Originally posted by rustyATV
Oh, and as for engine tuning, I actually had very little done to my cylinder. It was an 88 jug with flow work done to the transfers, on the underside of the cylinder. I also epoxied the two secondaries and raised them about 1/2 a degree (I think, it was a while ago and a friend told me how to do it). I also widened the exhaust slightly, but did NOT raise it.

That was it for porting. I also bored it out 0.080 over and used cool head to raise the compression to 185psi to max out on pump gas. I used an early model piston, so it was a base plate motor.

Other than that, a Paul Turner Type 6 pipe and a Keihin PWK 38mm Air Stryker carb, and '97 CR250 reed cage were all that was done.


thats is my exact setup except i had my squish set and stock head rechambered. mine runs on race fuel and the power is smooth and almost immediate. on hills i crack the throttle at the base and bam....its right there! im getting my motor rebuilt right now.this setup is at no dissadvantage to my 450r in the woods at all. i race the 450r just cause i love my 250r too much to beat it up.

[woodsracer144]

well i just got my new race quad... it was dark so i couldnt get very good picks... but i' post some of it tomorrow... i'll be rebuilding it.

any one know how long the a-arms would be at 49in? thats compressed... with 19In shocks. and 3-2 rims thanks

[86250rrider]

sounds like plus 2 but im not sure. better get 4/1 offset wheels for steering and NOT hitting trees. how wide is the back ? im at like 46.5 " with 4/1 wheels front and back with +2 arms. PICS?

[woodsracer144]

ill get some better pics tomorrow.