xr200 cylinder worn @ cam chain guide

7 replies to this topic
  • basilfaulty

Posted 23 November 2008 - 01:58 PM

#1


So I bought this bike with a cam chain issue. The more I take apart the more I find. Tensioner broke, loose piece spinning around behind flywheel wore a hole in the case internally. Crank has .045 runout at flywheel bolt area.

So I figure I am going to find a bottom end and use my top end..... took it apart today and found that the jug is worn at the front cam chain guide. Basically where the guide pins sit down into the jug 1 side is worn like double the size and allows the guide to move around. Anyone ever had one of these welded and machined again? I looked on ebay for a jug....none available at the present. Also looking for a bottom end or complete running engine. Any thoughts? I dunno which way to go on this one. And NO I don't want to put a Lifan engine in it!...LOL

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  • smrmx14

Posted 23 November 2008 - 02:49 PM

#2

what year you got I got some xr185 parts that should work.I am pretty sure I got a 200 cylinder but may need bored to the next over size.

  • basilfaulty

Posted 23 November 2008 - 06:16 PM

#3

MY xr is a 2001. I found a ottom end on ebay from a 1986...should work. Dunno what i am going to do with the jug yet. You have one?

  • chuck4788

Posted 24 November 2008 - 10:42 AM

#4

Old School Al stated in another thread:

"You want to find a 94 (engine # 5705049 on) - 02 case. Change in the right main bearing at this point. Early had press fit bearing ont the crank , and slip fit into case. Late (as you need) had press fit into case, and slip fit onto crank."

The part numbers for the right case did change in 86 and 96, so you should look for 96 and on. Or also use the crank from the 86.

  • basilfaulty

Posted 24 November 2008 - 12:27 PM

#5

I am going to use the complete bottom end from the 86 and put my top end on it. Well at least I WAS going to put my top end on it. Looks like I will put my head on it and try to find another jug to use. I don't know how much that wollered out hole for the pin will affect things if I use my old jug. Shame of it is other than that the jug is in real nice shape and stock bore. I mean this bike still has the original tires on it. I bought this one to for my wife. She likes my XR so I figured I would get her one. This was running when purchased...just noisy! Boy was I in for a surprise when I opened it up to check things out.

  • AntonLargiader

Posted 01 February 2012 - 10:02 AM

#6

Old thread I know, but I have the same issue. Our 2000 XR200R has always (we bought it used) had a noisy chain, and I can see that there is this sort of wear on the cylinder.

Basically, the guide rail has a support pin running across it about 1/3 from the top, and it seem that this pin is originally encased in plastic when the rail is molded. These pins sit in round recesses in the top of the cylinder.

In my case, the plastic covering has worn off the pins and the exposed metal has hogged out the recess in the cylinder somewhat. I'm replacing the rail anyway, but it would be a shame to trash the cylinder for this. However, I'm worried that the new rail pins will wear down quickly because they are not being supported by the correct shape. Also, the rail position will be slightly (maybe 2~3mm) farther away.

How normal is this, and do I need to repair or replace the cylinder? I'll post pics soon.

  • AntonLargiader

Posted 02 February 2012 - 08:30 AM

#7

Here are some shots of the worn parts. I'd like some feedback as to how normal this is, and whether or not I should just reassemble with a new guide.

The guide
Posted Image

Left side support
Posted Image

Right side support:
Posted Image

  • Old School Al

Posted 02 February 2012 - 10:55 AM

#8

A sign of a badly neglected 200! When there is a noise........... there is a problem! Don't use that cyl, get another one. Always want to check that area of the cyl when looking for a used one.

Old School Al



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