Jump to content
Antigravity Batteries Product Giveaways - LAST NIGHT TO ENTER! Read more... ×
Sign in to follow this  

1997 xr250 cylinder head main bearing

Recommended Posts

I just bought a project xr250 off a guy. It is about 85% restored. Rocker and Sub Rocker arms are shot, camshaft is shot, and the main bearing on the cylinder head looks rough. I brought it to a local shop, which i dont know much about, and they said it was trashed. They also told me that the cylinder head and cylinder head cover was a matched set. I would have to buy both. I then called a honda dealer and they said I COULD interchange heads and covers. "Any opinions on that issue". My main question is if there is any way to repair the main bearing on the cylinder head, or a place to find a cheap replacement. I would appreciate any help or comments fellas.

Share this post


Link to post
Share on other sites

Can you post a photo? If the damage is not too bad off, it can be lived with.

Share this post


Link to post
Share on other sites

Thanks. Ill see what I can do about a pic. Im new to this, I appreciate the reply. Have you ever heard of machining out the old bearing and installing some kind of a new bearing or is that even practical in your opinion

Share this post


Link to post
Share on other sites

Honda sells the head and cover as a set because the bearing bores are machined with the two parts assembled. Mixing parts is possible but will very likely result is mis alignment and a change in bore diameters resulting in too much bearing clearance and/or binding.

Welding to build up the bearing surface is not an option because the head is pressure cast which entrains hydrogen gas. Welding releases this gas creating porosity in the weld.

The bearing bores could be machined to accept bushings, the XR200 uses a bushing on the end of the cam that is pin located into the head.

Share this post


Link to post
Share on other sites

Thanks for the info. Is there a bushing made for that application? I have a friend that can machine out the bearing, if there is a bushing made for the XR250 main bearing. As of right now I am open to an suggestions as I really dont want to go spend $400 on another cylinder head. Thanks again.

Share this post


Link to post
Share on other sites

I have a basher of a xr100 we picked up cheap, the oil filter gauze in the bottom was blocked with cam chain tensioner debree, which restricted the oil to the cam.

I tapped and screwed brass screws onto the worn area and with patients and time used a die grinder and file set to bring it back to size. The cam now fits and runs well, the bike doesn't stop.

Go the xr !!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

  • Similar Content

    • By 661Bran28den661
      What’s up guys. Totally new here picked up an XR400R I live in the desert so I’m riding often and enjoy it. But I am having some issues with my  01 XR400R. I brought it out this morning for a putt and it seems to be choking up in the top of second. Like a bog an go bog an go. First seemed fine and third I didn’t make it high enough into the rpms to see. Before I brought it back to the garage. Yesterday I also changed the air filter back to an uni. I had seen the other one had a hole in it and the box was dirty gunned up and oily. I removed the airbox gave it a good clean out wiped everything down very well put a piece of screen over the snorkel Or where it used to be I should say. “Lightly oiled the filter.Also the spark arrester an tip for the bike it did not come with I ended up making one with a piece of flat steel and drilling holes. Whilst doing this. I found also a crack in the pipe. It almost sounds as like there’s a vacuuming or whistle? When revving.The first one I had made worked fine I had no issues. This one I am wondering maybe if it’s a cause of a little too much back pressure.So I’m assuming it’s either a Carb or exhaust problem. Or something that could totally be minuscule. Or major issue. Would definitely like some second opinions and any advice would be greatly appreciated. Thanks guys! 
      TWISTIN THROTTLES & CRACKN BOTTLES


    • By ddickinson
      My lanky 14 year old boy started showing an interest in riding MX/Off-Road so I sourced the best beginner friendly, yet dirt worthy, bike I could find: an Ol' Honda XR250R (2004). So far I've replaced a few clutch levers and perches with stock parts. That's gotten old and I'm looking to upgrade to an ASV or Torc1 type fold-able clutch/perch brake combo. Went to purchase online today and to my surprise there were no such parts listed for the XRs. I saw plenty of CRF/CRF-X choices and they seem to differ depending on generation. Obviously I can use nearly any perch/clutch combo as long as the two match; but I was wondering if anyone knew which of these levers was closest to stock? Also, will the first gen CRF250X brake lever work on the XR? These may be stupid questions to some; but I'd rather ask a dumb question than drop money on an ASV brake lever I can't use. Thanks for any help.
      #xr250r#hondaxr  
       
       

    • By TheLastByte
      Im currently in the market for an xr400r, and considering buying one that's had some heavy engine work done. The current owner claims to have bought it from a friend who's an XR enthusiast. The PO installed a big bore kit and high comp piston, as well as a xrs only pumper carb, rsw triple clamp, aftermarket clutch, street lights, and a whole bunch of bling.
       
      My main concern is the effect the upgrades will have on the engine's longevity. How much quicker will I be going through top ends with the setup on this bike as opposed to a stock setup, and should I be worrying at all about bottom end longevity as well? I wouldn't mind having to eventually redo the top end, but I don't want to deal with a race bike type top end rebuild schedule on an XR. 
      Is there anyone here who's running a bike similar to this one who can give some advice? 
    • By Ralph303
      I have a 2001 Honda XR400R. It has a whirring/grinding sound in the lower end and a vibration in the top end. I pulled the valve cover and everything looks good. Decompression lever looks to be in order. Anyone know where I should start looking or just rebuild the whole engine. Ballin on a budget, but really love this bike. It looks like it’s new otherwise. Oil was jet black and thin. Thanks in advance! 
    • By junglePIG
      Hi, I have an Xr250r with a buckled/ wobbling front wheel, after trying to true the rim i have broken a spoke.
      I am wondering if it is possible to lace any 36 hole aftermarket rim to the oem hub, also will i need to buy an xr250r specific spoke set. also could i take a 36 hole rim from another front wheel and lace that up???? thanks
×