250R Hybrid?

[bubbag]

Hello,
I bought my dream quad a mostly original '88 250R, Then one month later the new 450's came out and I got whooped.
I then stripped the quad to the frame and welded it. I then modified the quad with basically everything (to the tune of 12,000 canadian including buying the thing).
Now I'm having problems with the motor and I'm starting to think I might be better off buying a used 450 dirt bike and putting the engine in the R?
How hard is this, my father is a very expieranced welder and I have a shop with everything for tools that would be needed.
Should I just try and find another R frame and modify it to except the new engine (I don't want to hack a good R frame that was just powdercoated).
Also could I interchange any of the parts I already have and put them on a new trx450R and just part out the R?

[zedicus00]

with that much money in an r it should whoop a 450R. what type of problems are you having with the motor? if you want to do a hybrid i would buy a frame designed for whatever engine u want with 250r geometry. no point in hacking up a good stock r frame. but my (biased) opinion is keep the r with the 250r engine in it and fix it, whenever u make sumthing thas almost 20 years old start putting out more power yur bound to find the week links quick. just build it up an u will b happy with it.

[bubbag]

Well for mods I have the following:

Ricky Stator +2 a-arms
Streamline Stainless brake lines.
FMF Fatty Exhaust
ESR Keihin Airstryker carb
ESR Airbox Eliminator kit
Boyeson reeds
Lonestar Axle
Renthal Bars
TCS Triple Rates W/rezzys
TCS Dual Rate Rear Shock w/rezzy

[bubbag]

Well For engine problems, I just got the top end rebuilt and now I can't get the damn thing started (it is gettting spark).
And I put the stock airbox/snorkle back on in hopes of getting the bike to richen up. As the reason that it was just rebuilt was due to the engine leaning out and scuffing up the exhaust side of the cylinder, this was when I had the airbox on and no snorkle hooked up. As for the esr Airbox eliminator kit when I had it on prior to blowing up the top end would not get rich not matter how big of a main jet I put in it (I went upto a 210).
So I have had the bike for a year and have already rebuilt it twice and I'm getting sick of the hassle, that is why I'm thinking of getting a 450 motor.

[zedicus00]

maybe there is an airleek sumwhere an it is causing it to run lean? thas a nice quad i hate to hear about problems like that. also maybe yur carb needs rebuilt or just try a new carb. theres a bunch of little things it could be, but stick to it and im sure u will get it figured out.

[bubbag]

Here is a before pic of the quad...

[zedicus00]

well u did a very good job on the rebuild, check yur pm box.

[bubbag]

Ya I think the first Rebuild I did, didn't last due to an airleak at least from what I have read now.
As for the carb it is a ESR 38mm Keihin airstryker and it is brand new (I have only ridden this bike for like maybe 8hrs after the restoration).

[zedicus00]

they can b a bear to start on the first time, try pull starting it if u r sure yur jetting is pretty close. i know a lot of peeple that do that. make sure to break it in really good b4 you rip on it too.

[bubbag]

The reason I didn't pull start it is because I was worried it might not be good for a engine that was just rebuilt and nothing has any run time on it? or am I good to give her a pull?? :confused:

[zedicus00]

it wont hurt it jus dont go real fast on the pull start and dont do it everytime u go to start it. but yea the very first time it will be fine. did u do a compression test? and what octaine gas u got in it?

[bubbag]

It has 91 octane in it right now, and What should I mix the oil ratio at? I was told 32:1 is too lean?
I have Belray HR1 Synthetic premix oil....
I did a compression test with a cheapo tool and got 128lbs of compression??? This is with a Wiseco pro-lite on a .50 over bore....

[zedicus00]

OUCH! okay from the begining. dont use that belray oil it will gum stuff up over time. golden spectro, klotz, and castor 927 are sum of the best. mix ratio of sumwhere between 40:1 and 60:1. and premium gas so yur octane is fine. yur compression however is WAAAY low. especially right after a rebuild. provided you are using a stock style head gasket and a stock unmodded head u should b around 165lbs compression. ive seen them run with 140lbs compression gut even then it aint good. yurs is way off man maybe it broke a ring or sumthing? did u get the piston in the right direction? all the gaskets sealed up good? not getting water in the topend or anything?

[bubbag]

I thought that was low #'s But each time I have the bike running it usually reads 120's to almost 130lbs... I have questioned both shops that have rebuilt it and both said that 125lbs is normal on these engines???
Everything is stock on the cylinder (not ported, stock size gaskets,head is not shaved).
Could this be my problem?????
The bike read this compression # when I first bought it too...

[zedicus00]

i cant believe it... i could maybe see it running with thouse number but not running well and not running long b4 it quite completly. stock compression on a bone stock engine is right around 160, usually after its rebuilt and bored and stuff it will go up too, with the gasket out of a cr dirtbike you can raise the compression even more withought any ill effects. i would say first, dont ever take it to the shops that gave you that information. and second. you need to get it redone 1 more time. dont take it to just any machine shop.

[bubbag]

Both Shops were Honda Dealerships, and I don't wanna have to rebuild it again I haven't even rode it yet with the new piston :mad: So I'm gonna try and call Wiseco and see what they have to say because this is bull**** I have argued with each dealership and they both claim that 120-130lbs is a healthy 2 stroke engine :mad:
What can I do.....??

[zedicus00]

take that new piston and stuff it up there *****. that may be good compression on a weed eeter but that is WAY off on an R. maybe get a shop manual for an R take it to the dealers and show them then make them fix it right. its going to hav to b bored again and a new piston becuz it needs to be set up TITE. an R engine needs rebuilt befor the compression gets down below 140 or the piston slap from the loose piston in the sleeve could cause the skirt to break. (ive done that b4, it really sucked) oh, give the fone number to an R engine builder like ESR to yur local dealer an make them call an ask what the engine should be set up like.

[zedicus00]

just as a comparison i run my engine at 185lbs psi. on pump gas. i know a lot of people who run as high as 225lbs but they hav to use race gas. i hav heard of a few people running upwards of 270psi.

[bubbag]

I just tried calling Wiseco tech and I'm awaiting a tech to return my call :mad: I called ESR and they said that is a low # but will not allow me to use them as a reference in the matter :rolleyes: I called another local snowmobile performance shop and they said that # is normal on R's that they have rebuilt.

[zedicus00]

seriously i would like to c an R run with that low of compression, i can check my service manual tonight and see if it says, then maybe i can send you a copy of the page with it on it or sumthing. try calling CT, baldin motor sports, o and eric gorr at forward motion racing, im sure he would let u use him as a reference and he knows his stuff. check out thouse links i sent to you private message box too.

[wilkin250r]

I understand your frustration and anger. Nobody likes a hassle quad.

Honestly, before you scrap the whole project for a 450, I'd give it one more shot. Send the entire motor and carb to a high performance shop, somebody with lots of experience with the 250r, and let them go through it from top to bottom. It will be expensive, but not nearly as expensive as buying a new 450.

You might even consider sending the whole quad in to a shop. That way, not only can they rebuild and check out the motor, but they can also test it and make sure it's running properly.

I just really hate to see anybody give up on a good 250r.

[bubbag]

Thanks for the help guys,
I'm going to try and get a better gauge to run a compression check and see if maybe that is the problem. I have wanted a 250R ever since I was 12 so what has kept me with this project is just that the R is sentimental, even 8 years later.
I think that I'm going to start looking for a engine builder and just send the motor complete to them and let them go through it.
And try and get some ride time on it until I have enough cash to do that complete big bore setup.