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98 XR250R cam chain help (Inside pics!)

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Well now that I'm keeping my XR, I might as well get down to business and replace the slappy cam chain.

I'm wondering... Do the auto tensioners on these things ever fail? Should I order a new tensioner along with a new chain?

Also, can I just pop the valve cover off and snake a new cam chain in? Or is it more involved than that? What exactly do I have to do? The service manual does not show how to replace a cam chain as far as I've noticed.

Edited by gabechroust

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The only thing to fail on the 250's tensioner that I've ever read about is the spring.

I think you're going to need to take off the right side case cover. Look on page 4-3 of the shop manual. See how the clutch basket and oil pump drive gear have to come off to get the chain off.

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Alright I just took the valve cover off. HOLY SMOKES! This thing needs help! Never thought it did because it ran like a champ :banghead:

Check out Mr. Right Hand Exhaust Rocker!!! Looks like he's lived a hard life :lol:

DSC00601.jpg

Then check out the gash on the right hand exhaust cam lobe!

DSC00600.jpg

Looks like it's definitely time for a new camshaft and new rockers! New OEM is going to be expensive.:) How could this have happened?

I noticed this button on the chain tensioner. What the heck does it do? How do I check that the tensioner is good?

DSC00602.jpg

DSC00603.jpg

It looks like I can almost pull the chain off the sprocket with my fingers. I'm sure I could if I pushed it to the side and turned the engine to derail it.

DSC00605.jpg

DSC00604.jpg

Anyone have a stock cam they want to get rid of? I need one. Don't want to go the aftermarket route for fear of this wear happening again. Baja Trail Rider told me that there's a cam he uses that is very low wear. Is there any others like that?

Wow, was shopping for a stock cam and cam across this. http://www.ebay.com/itm/XR250R-Honda-Cylinder-Head-Rocker-Box-Rockers-Cover-XR250-1996-2004-XR-250-R-98-/400241183897?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item5d303bcc99

Looks like my XR isn't the only one to fry the right exhaust rocker.

Edit #9000: The cam in my XR says HOT CAMS WW-HCFF No.6 Hmmmm...

Edited by gabechroust

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As the cam chain wears, the spring on the tensioner pulls the rear wedge down into the body and he front button is also a wedge that keeps the rear wedge from sliding up in the tensioner body thus keeping constant tension on the chain. The fact that the rearmost wedge is sunk down into the tensioner body indicates that the tensioner has reached its' maximum travel due to chain wear, the chain is shot. If you don't have one, I highly recommend that you get a factory service manual, it is invaluable for avoiding mistakes and achieving a successful rebuild/repair.

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As the cam chain wears, the spring on the tensioner pulls the rear wedge down into the body and he front button is also a wedge that keeps the rear wedge from sliding up in the tensioner body thus keeping constant tension on the chain. The fact that the rearmost wedge is sunk down into the tensioner body indicates that the tensioner has reached its' maximum travel due to chain wear, the chain is shot. If you don't have one, I highly recommend that you get a factory service manual, it is invaluable for avoiding mistakes and achieving a successful rebuild/repair.

Thanks, that makes perfect sense. I have a Honda service manual, but it didn't say anything like that. It really has nothing about the cam chain or tensioner, which is why I had to post.

I think the timing may be off a bit too but it might just be due to the crapped out chain. Any suggestions on brands for a new chain?

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Any suggestions on brands for a new chain?

OEM. The CRF450 chain is beefier and less expensive. Fits the XR400. If they fit the 250 also, might consider that option. These 250 guys will know.

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OEM. The CRF450 chain is beefier and less expensive. Fits the XR400. If they fit the 250 also, might consider that option. These 250 guys will know.

Thanks. A thorough search just now churned up this thread: http://www.thumpertalk.com/forum/showthread.php?t=924217

Confirms that CRF450=XR400=1995 XR250R. But does 1995 XR250R = 96-2004 XR250R? It would be nice to have a cam chain on there that would never stretch again!

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I looked up a few cam chain part numbers at ServiceHonda.com, my favorite on-line moto parts dealer. These are part numbers only (and links where noted). If two cam chains have different part numbers, they may not interchange. There is no way to determine if they are interchangeable unless you have both physically in your hands and try them. If they are different lengths, they will not interchange, of course. I do not consider them interchangeable if you have to shorten one to fit. Some riders do not let that deter them at all. :lol:

Service Honda Cam Chains

XR250R 102L???

84-95...14401-KK1-003 and 14401-KK1-003 and 14401-KZ1-671

96-04...14401-KCE-671

XR400R

96-04...14401-KCY-671 112L

CRF250R

04-09...14401-KRN-671 104L

10-11..14401-KRN-A41 106L

CRF250X

04-09...14401-KRN-671 104L

CRF450R

02-08...14401-MEB-671 112L

09-11...14401-MEN-A31 108L

CRF450X

05-10...14401-MEB-671 112L

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I haven't seen a chain that doesn't stretch. It takes a while, but eventually it will need to be replaced, usually the 1st thing to wear out on a properly maintained RFVC engine. I personally prefer the OEM chain, opinions vary. As TR42 points out, it is not unknown for the tensioner spring to break, inspect it carefully. The spring is available separately, good idea to replace it. About Hotcams.....looking from a reliability standpoint, I am a fan of keeping the stock cam. If you want more oomph, a 77 or 78mm overbore using a Wiseco piston in conjunction with a pumper carb (kinda pricey) is a big improvement.

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I looked up a few cam chain part numbers at ServiceHonda.com, my favorite on-line moto parts dealer. These are part numbers only (and links where noted). If two cam chains have different part numbers, they may not interchange. There is no way to determine if they are interchangeable unless you have both physically in your hands and try them. If they are different lengths, they will not interchange, of course. I do not consider them interchangeable if you have to shorten one to fit. Some riders do not let that deter them at all. :bonk:

Service Honda Cam Chains

XR250R 102L???

84-95...14401-KK1-003 and 14401-KK1-003 and 14401-KZ1-671

96-04...14401-KCE-671

XR400R

96-04...14401-KCY-671 112L

CRF250R

04-09...14401-KRN-671 104L

10-11..14401-KRN-A41 106L

CRF250X

04-09...14401-KRN-671 104L

CRF450R

02-08...14401-MEB-671 112L

09-11...14401-MEN-A31 108L

CRF450X

05-10...14401-MEB-671 112L

My chain is 102L. I guess I'll just stick with an identical OEM replacement.

I haven't seen a chain that doesn't stretch. It takes a while, but eventually it will need to be replaced, usually the 1st thing to wear out on a properly maintained RFVC engine. I personally prefer the OEM chain, opinions vary. As TR42 points out, it is not unknown for the tensioner spring to break, inspect it carefully. The spring is available separately, good idea to replace it. About Hotcams.....looking from a reliability standpoint, I am a fan of keeping the stock cam. If you want more oomph, a 77 or 78mm overbore using a Wiseco piston in conjunction with a pumper carb (kinda pricey) is a big improvement.

I'll be ordering a tensioner spring in case. Yeah, I wont have anymore of this HotCam crap in my XR250R. Valve clearance adjustments were always too soon and now this. OEM please.

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Yeah, I wont have anymore of this HotCam crap in my XR250R.

I'm not to praise HotCams, just be sure the cam/drivetrain wear is not because of neglecting the bike by the PO. I've purchased my XR4 with 8k kms, the stock cam had some nasty damage, the bike was run for who knows how long with no clearance at all on one of the exhaust valves, the extra stress/heat killed that lobe.

My stage1 cam after 2k kms still looks like new, I've had it in my hand when installing the 426 a few days ago.

As far as I've read the reported hotcam failures could be connected to running with no oil and the like.

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Just ran across this thread, I did a top end with a 280 kit and cam chain/tensioners last summer, Yes YOU NEED a New Tensioner they do get warn out. The cam chain actually wears/grooves into the tensioner and guides

as well as the spring is not as tight as new.

I sent my Head and Jug to XR's only for the bore and new 280 piston :smirk:.

all I had to do was install it and the new cam chain/ and tensioner.

The 280 kit really wakes this trail bike up!!:bonk:

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I'm not to praise HotCams, just be sure the cam/drivetrain wear is not because of neglecting the bike by the PO. I've purchased my XR4 with 8k kms, the stock cam had some nasty damage, the bike was run for who knows how long with no clearance at all on one of the exhaust valves, the extra stress/heat killed that lobe.

My stage1 cam after 2k kms still looks like new, I've had it in my hand when installing the 426 a few days ago.

As far as I've read the reported hotcam failures could be connected to running with no oil and the like.

From what I've read, aftermarket cams on the XR400R are perfectly fine but the XR250R can't handle higher lift than stock. If it weren't a confirmed problem, I sure would just throw another Hot Cam in!

Just ran across this thread, I did a top end with a 280 kit and cam chain/tensioners last summer, Yes YOU NEED a New Tensioner they do get warn out. The cam chain actually wears/grooves into the tensioner and guides

as well as the spring is not as tight as new.

I sent my Head and Jug to XR's only for the bore and new 280 piston :smirk:.

all I had to do was install it and the new cam chain/ and tensioner.

The 280 kit really wakes this trail bike up!!:bonk:

Thanks for the info. I'll check out the tensioner to see if it's too worn in. I did buy a new tensioner spring just in case anyway. Just waiting on the parts I already ordered now.

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Got the parts, took the bike all apart, and GRRRRRRRRRR even more problems.

Cam chain tensioner isn't too worn in... BUT IT'S BROKEN!!! The slider part that the spring attaches to is cracked, so the spring was just dangling in there. :bonk:

I am beyond lucky that the cam chain didn't fly off and have the valves crash into the piston.

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Reviving this thread rather than starting a new one.  I am in the process of putting a 277 kit in an 03 XR250R.  The problem I am having is with the cam chain tensioner.  The rear wedge is sticking up 1/8" or so, but I can't seem to get a good enough grip on it to pull it up and slip a pin into the hole to hold it up.  The chain seems tight, can't pull it off the sprocket, so I wasn't planning on replacing the chain.  Since I can't seem to get a good grip on the tensioner wedge, can I unbolt the tensioner at the pivot point behind the cluth and pull it out to take tension off the chain.  I'm kind of stuck here with what to do.  BTW, I can't seem to find a new tensioner or chain online for this bike.  Any suggestions as to what to do at this point?

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DiscountHondaParts lists the parts and prices; call them to verify availability.

 

http://www.discounthondaparts.com/fiche_section_detail.asp?section=2484076&category=Motorcycles&make=Honda&year=2003&fveh=131720

 

1-800-955-2925

 

PS  Use visegrips to pull the wedge up; heavy duty, quality, visegrips.  Use a paper clip in the hole...

 

:ride:

Edited by ramz

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ImageUploadedByThumper Talk1406039337.276828.jpg

Here is a picture of an old chain, the tensioner a rear wedge that you're supposed to grab and put the paper clip in is sunk down and it couldn't grab it.

When I put my new chain on, the rear angled wedge on the tensioner was taller than the square wedge next to it.

The chains (compared by dangling both from my finger) were the same length though.

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Thank man. I just bought a 94 250r for 2 bills and the kick start would hang up close to TDC so I tore it down and realized someone had a fresh top end rebuil on it but I think they either didn't set the time right or just used an bad chain cause it jumped time and bent the intake valves. Not to mention whoever did the build they lost atleast 5 or 6 bolts in the head including the pins keeping the cam from sliding. I wanna be sure so it doesn't jump time again so a new timing chain is in need it seems.

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I know this is an old thread, but I recently came here looking for a picture of the wedge height when new...couldn't find one, so I thought i'd upload one after the job. Cheers

 

20160423_155731-sm.jpg

20160423_155736-sm.jpg

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