ah, another question.

[Showcase]

hello, i have a 87 250r, it has a 295 big bore kit on it. compressions around 220. i have had nothing but problems with it. and paying for race gas! haha. =/ well the latest problem. the flywheel bolt kept coming loose. i couldnt get it to stay on. so i used an air wrench. stupid me. and mustof over tightened it. then it ran for a little bit. but kept cutting out. would start to run again and cut out...like the timing was off. i have some pictures of the bolt after i got it off this time.

[img=http://img166.imageshack.us/img166/1241/threevs8.th.jpg] (http://img166.imageshack.us/my.php?image=threevs8.jpg)
[img=http://img409.imageshack.us/img409/5688/sixlk0.th.jpg] (http://img409.imageshack.us/my.php?image=sixlk0.jpg)
[img=http://img170.imageshack.us/img170/5581/sevenwt2.th.jpg] (http://img170.imageshack.us/my.php?image=sevenwt2.jpg)
[img=http://img501.imageshack.us/img501/5949/oneqv5.th.jpg] (http://img501.imageshack.us/my.php?image=oneqv5.jpg)
[img=http://img181.imageshack.us/img181/2599/fourzg7.th.jpg] (http://img181.imageshack.us/my.php?image=fourzg7.jpg)
[img=http://img261.imageshack.us/img261/7584/fivesm3.th.jpg] (http://img261.imageshack.us/my.php?image=fivesm3.jpg)

[Showcase]

another thing is that i just got a new 150w ricky stator stator. only like 20 minutes of time on it. .and what im wandering is, idk if thats fixable, if i have to get a new crank and rebuild it. how much would it cost? i htink i could do it myself. but i wanna lower the compression for lower octane. and make it more of a woods bike.

[peeping TOM]

real blurry photo's ...so are u saying u've damaged the threads ?

[Showcase]

yes, you cannot thred the bolt back on. sorry that wasnt clear.

[cdrookie]

yep, new crank

[86 Quad R]

i've actually managed to salvage a crank stipped as yours is using the next size smaller dye to recut threads

[Showcase]

for a new crank i have to pretty much rebuild the whole motor correct?

[Master LTR450]

Rebuild the whole motor No, recommended why its apart Yes!! You will have to take the whole motor apart so why not rebuild it now instead of 2 months down the road if something else goes??

[Showcase]

very true..while im at it i wanna make it so i can run regular gas. how would i change it for that?

[LONG-ROD]

Get rid of the ricky stator, I have heard of people haveing lots of problems with them, to run pump, 50/50 my recomendation. You need to lower compression by running a bigger dome, if you have a stock head that has been milled you will have to get a new one, if you want a good reliable motor I would get a diffrent cylinder with a stock sleeve, I am guessing you have 310 sleeve in a stock cylinder, when you bore them as big as yours is you have head gasket issues, and the head I think had to be rechambered for the water jackets. I am sure someone else will chime in soon and clear this up better for you.

[mxduner]

Originally posted by Showcase
very true..while im at it i wanna make it so i can run regular gas. how would i change it for that?

do you have the pro-x cylinder kit or stock cylinder? i probably have what you need.

also make sure your key is in good shape, even though thats the least of your problems, but like like 86 said, run a dye, you just had that motor rebuilt(if i remember correctly) good luck

[deathman53]

I was told that when the flywheel nut keeps coming loose and off. The crank bearings are going, the nut loosens because of vibration in the crank.

[86 Quad R]

Originally posted by deathman53
I was told that when the flywheel nut keeps coming loose and off. The crank bearings are going, the nut loosens because of vibration in the crank.

if that were the case then the flywheel nut on a CR engine wouldnt ever stay on there lmao but on a serious note. chances are that the threads were in a bad way already and thats why it backed off/stripped.

as i previously mentioned, you can re-tapped and a slightly smaller nut used. with a bit of lock tight it should be fine. :cool:

[Showcase]

it is the pro-x cylinder, its a 295 big bore.
thanks for the replys.

[Showcase]

okay, i tried re threading it and it did not work, i think im just gonna redo the engine. ill have to do it myself. and i dont have a whole lot of money to put in it. im thinking a new cylindar, maybe stock? make it so i can run regular gas and such. how hard would it be to rebuild it? i have all the tools i would need. ive never really done anything bigger than mowers and such. i feel pretty good about my engine knowing. any suggestions what i should be getting? and from where/

[mxduner]

run only oem crank. and switching to run pump gas is EASY, depends on which head your running, stock or aftermarket.(cool head ct etc.) which you probably have. and i have a new dome you need.

[2muchquad]

You wont have to rebuild your motor due to damaged threads.I have come across many motors before in the past with chewed up crank threads from cross threading to mushroomed from hammer blows.You should be able to find a self starting nut that cuts it own threads to use,rebuilding a crank for damaged threads is silly.I have never had a flywheel loosen up after repair.;)

[Showcase]

so i should just keep looking? . its a cool head. the dome in there now is a 20cc im pretty sure. i have a 19cc also.

[86 Quad R]

i too have never had to replace a crank due to screwed up threads. as mentioned i've never had a nut to back off after a repair. what needs to be done prior to running a threader on there is to take a small flat file and work the top of the threads "ever so carefully" (at the end of the crank) so that it creates a better area to accept the dye much better and will allow it to start much better and SQUARE.

as for thew lowering of compression..... i'd figure out exactly what head you actually have and buy larger domes to decrease the C/R. hope this helps..... goed luck. :cool:

[mxduner]

Originally posted by Showcase
so i should just keep looking? . its a cool head. the dome in there now is a 20cc im pretty sure. i have a 19cc also. I have a 21 or a 23cc dome thats new. that got my 310 motor to 160 -170 psi. thats about what you need for pump gas.might just have to trade with you. If you are not comfortable with rethreading the crank, pull the motor out and bring it to bill bune, he does amazing work. hes right behind hardees off 7th and main, cant imagine him charging much too repair that thread. hope that helps.