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Ndog
04-19-2009, 10:56 AM
Hi guys....been a while since I have been on here but need some help.
I have a 1985 atc250r that I restored partially last year. I send the top end to Eric Gorr and had him do a number on it, installed ESR reeds, ESR pipe n muffler, 38mm PWK stryker, new clutch, rebuilt forks, new rear shock, new bearings, tires, rebuilt brakes, durablue extended axle, lonestar anti fade axle lock, lonestar double row axle housing.......did alot to it. It was hell changing the axle..the rear end was totally rusted and fused together. I literally had to cut the carrier out with a cutter one little chunk at a time! Very tedious

Anyway..I was so pleased with my trike after all the hard work...it was a monster. Handled like mad on the flat track and the front end would come up at will, even low in 6th. By far the funnest vehicle I have ever owned. Vowed to never sell it. This season I had planned on powdercoating the frame with fresh Honda Red and refinishing the plastic to complete the trike. Then IT HAPPENED....

My brother was opening it up across the front yard and it locked up and skidded to a stop. I was heartbroken....did I catch a ring...did the tranny lock up...was it the crank???? Well, last weekend I took it apart to find a completely blown up crank. This crank was in pieces...with the main failure being right around the big end bearing!!!!!!!!! There was bearing pins in my exhaust pipe this thing blew up so bad!!! The piston skirt was pancaked but amazingly the cylinder is untouched (thank God). So now, I have the motor off and ready to split the cases and do this baby. Good time to strip the rest and get the powdercoat I guess. My questions are:


Aside from gaskets, crank, bearings, piston and rings is there anything else that might need replaced from such a failure? (like counterbalancer etc...)

What crank/bearings are the best?

Should I replace any other components at this time since I have the motor out?

My cylinder looks untouched..do I need to have it honed before a but a new piston/rings in?

Im gonna get the frame powdercoated...can I drop the front end and rear end off in one piece each to minimize work during the frame stripping?

Thanks a ton guys...this sucks but I know if it was screaming with a beat up old 85 lower end (i suppose) that it is going to be amazing with a new setup.

Ndog

beets442
04-19-2009, 04:41 PM
You'll probably need seals. I would hone. Sorry about all the ?'s, wondering why the bottom locked.. What ratio were you running? Ports chamfered? What kind of oil? Was it broke in? I change my oil and clean filter after the first hour and do it again after 3hrs, just to make sure of a clean break-in.... Beets

JohnR.
04-19-2009, 08:58 PM
I would only use OEM Honda bearings and seals in the bottom end. There's too much at stake to try to save a few bucks. From the last sentence of your post it sounds like you still had the stock bottom end in it, that's answers the question of WHY it happened.

I'm not sure what you mean by "drop the front end and rear end off in one piece each" though.

John

Ndog
04-19-2009, 10:58 PM
Should I get a stock crank or aftermarket?

Should I get stock piston or wiesco or what?

JohnR.
04-20-2009, 09:03 AM
If it were my machine, I'd get a Wiseco crank with the longer (87-89 TRX) rod on it, a Wiseco piston for the ATC, and then run a spacer plate on the base of the cylinder. A longer rod improves your rod angle which gives you better durability (less wear) and the spacer on the base increases your crank case volume for a little more power.

John

aaron7
04-20-2009, 11:31 AM
Hot Rods makes a nice crank kit:

http://cgi.ebay.com/ebaymotors/Honda-ATC250R-TRX250R-Hotrods-Crankshaft-250R-Crank-ATV_W0QQitemZ370184305779QQcmdZViewItemQQptZMotors _ATV_Parts_Accessories?hash=item370184305779&_trksid=p4506.c0.m245&_trkparms=72%3A1205%7C65%3A12%7C39%3A1%7C240%3A131 8

Ndog
04-26-2009, 01:00 PM
Ok guys...I am getting ready to order a Hot Rods crank.

For bearings...are All Balls Bearings good or should I get OEM.

Also, should I get OEM gaskets or aftermarket?

Finally, this crank failure happened on a top end that was fairly new. The piston was damaged so I am getting a new one and since im in there throwing on new rings. DO I NEED TO HONE MY CYLINDER BEFORE NEW RINGS? If so, where can i get a honing attachment?

Cant wait to get started...thanks

Ndog

ceaserthethird
04-27-2009, 04:57 PM
Well let's see some pictures of the Tear Down & rebuild Lot's of them PLEASE !

Yes Get OEM Bearings & Seal's - List a total price ?

I would go with OEM Gaskets ...

Ndog
04-27-2009, 06:15 PM
I got a ton of stuff ordered today!!! Got all OEM stuff except for a Wiseco Pro-Lite piston. Went with the TRX long rod bc the ATC Rod is discontinued so paid 283 for the TRX crank from service honda.
Got the red spacer plate to lift the cylinder up for the longer crank. I got all new bearings and seals for the internal components and even steering stem bearings and stuff bc I am about to gut the front and rear off the frame and go GET SOME HONDA RED POWDERCOAT!!!

With my new frame and motor all my new components will finally not look out of place. I also get to finally match my case to my totally reemed cylinder!!! WOOH HOOH :) Stuff will be here in about a week. Gotta go strip my frame n get it to the powdercoaters!!

LOTS OF PICTURES GUYS and I will also write about the differences I felt with the TRX crank/base plate combo.

MTS
04-27-2009, 06:32 PM
Get the cyl measured, see if its out of round or taperd, wore ect, if everthing checks out a hone will be all ya need.

Ndog
04-29-2009, 03:31 PM
AAAAAAAAAAHHHHHHHHHH!!!

I was so excited as I broke the last bolt....had the whole frame stripped with no casualties. Not bad for a 24 year old machine that had been thru hell........

Then it happened....as I tried to pound the swingarm bolt out with a hammer and wood block.....IT WASNT GOING ANYWHERE!!

I went to the bolt head side and put my 19mm socket on it...nothing. Even bounced on the ratchet with my 200lb body...nothing.

Sprayed penetrating spray with it on its side and let it soak all night...nothing.

Heated it up and let it cool with a MAP torch....nothing.

Ive read all the horror stories and methods. Im going out of town for 4 days and was hoping to drop the frame off at the powdercoat place..not gonna happen. So I am letting it soak while im gone.

Looking like I am gonna have to cut this thing out guys :(

Im takin lots of pics tho haha