XR650L: Protect Your Countershaft Splines with an XR650R Sprocket

[SpudRider]

I frequently examine the countershaft splines on my XR650L. However, I admit, my eyes aren’t as good as they used to be.? Advancing into middle age, I’ve acquired presbyopia. ? The last time I inspected the countershaft splines, they appeared quite good to my unaided eyes. Therefore, after I greased the countershaft splines, I took a few photographs, and went riding.

However, I had noticed a hint of rust on both the countershaft, and the sprocket. Rapidly approaching 10,000 miles on my bike’s odometer, my nagging conscience prompted me to examine the photographs I had taken. Closely examining the macro photos, I thought I detected some countershaft spline wear.

Therefore, I went outside, removed some grease, and examined the countershaft with a magnifying glass. Indeed, I discovered the countershaft splines were beginning to wear.

Closely examining the Parts Unlimited sprocket I had just removed, I believe I also detected some wear on the trailing edges of the inside teeth.

Previously, I drank the XR650R, countershaft sprocket, Kool-Aid. ? I had planned to wait until my current countershaft sprocket needed replacement before making the switch. However, I now decided to act immediately!

I had shortened my drive chain to 108 links with my current 13T/45T sprocket combination. Therefore, I needed to acquire a 13T, XR650R, countershaft sprocket as quickly as possible. I did some research, and discovered I could obtain a 13T, PBI sprocket in 24 hours. The XR650R countershaft sprocket has 60 percent more contact area with the countershaft than the XR650L countershaft sprocket. ?

Mounted backwards, the sprocket teeth of the XR650R sprocket are 2.5 mm farther from the engine. Based upon the experience of others, I don’t think this will present a problem. In any event, I am perfectly willing to accept greater sprocket wear, and/or greater drive chain wear, rather than any additional wear on the countershaft splines.?

I needed to tap lightly on the PBI sprocket with a hammer to allow me to install the sprocket retainer. ? Heeding Dave’s admonition regarding PBI sprockets, I examined the alignment of the sprocket retainer. The alignment isn’t perfect, but it should be robust enough.

I went for a ride, and everything felt good. I will routinely inspect the drive chain, and both sprockets for unusual wear. More importantly, I am going to routinely inspect the countershaft splines under magnification to ensure I have stopped the wear. ?

Spud

[n16ht5]

I followed suit. thanks for shooting pics. I grabbed a 15t though, for highway. I think I'll look for a 13t as well for trails

[scalejockey]

I went one step farther...My sprocket came with a 'new' R.

Had a kid at the counter tell me that they didn't have the R sprocket and that the L sprocket would work fine:lol:?

[jonr3]

Are any brands better than others? I currently have a SunStar and looked at PBIs, and I'm sure there are some more out there. Recommendations?

[ThumpNRed]

I went one step farther...My sprocket came with a 'new' R.

Had a kid at the counter tell me that they didn't have the R sprocket and that the L sprocket would work fine:lol:?

It would work fine... Then we could explore the inside of an xr650r when your counter shaft takes a dump.

[SpudRider]

Are any brands better than others? I currently have a SunStar and looked at PBIs, and I'm sure there are some more out there. Recommendations?

I have read reports indicating the retaining plate is very easy to attach for the XR650R sprocket manufactured by Sprocket Specialists. Apparently the XR650R sprockets sold by JT Sprockets and Moose Racing are a little thicker; both these sprockets require a very light tap on the sprocket with a hammer before you can install the XR650L retaining plate. My XR650R sprocket manufactured by PBI must be thicker yet; it required a good bit of tapping with a hammer before I could attach the retaining plate. ?

Spud

[SpudRider]

I followed suit. thanks for shooting pics. I grabbed a 15t though, for highway. I think I'll look for a 13t as well for trails

You're welcome. ? Based upon my research, I believe the following manufacturers produce 13T countershaft sprockets for the XR650R motorcycle.

Moose Racing: Part #M602-20-13

AFAM: Part #20517-13

Sprocket Specialists: Part #617-13

PBI Sprockets: Part #50-386-13

Spud

Edited March 22, 2011 by SpudRider

[zx12r]

You're welcome. ? Based upon my research, I believe the following manufacturers produce 13T countershaft sprockets for the XR650R motorcycle.

Moose Racing: Part #M602-20-13

AFAM: Part #20517-13

Sprocket Specialists: Part #617-13

PBI Sprockets: Part #50-386-13

Spud

I've had the Moose Racing 15t xr650r sprocket on for a season and a half and the splines look fine, no noticeable wear. I did notice that with the OEM cs sprocket the inside of the teeth (facing the crankcase) had wear from the chain and the outside of the teeth had no wear. that has now switched, the outside teeth of the Moose Racing 15t R sprocket now has slight wear and the inside looks untouched. also my chain adjustment intervals have gone from every 5 rides with the new oem cs sprocket to every 20 rides with the moose racing cs sprocket, with the same chain (although, i think the chain wearing into the nylon collar on the new oem sprocket accounts for the quicker chain adjustment intervals).

[Purcell69]

I stumbled across this very thing a few years ago by accident. I had ordered a new sprocket from my 2007 XR650L, as I was wanting to play around with a 14 tooth to see how it worked out. I was on E-Bay, not paying attention, and bought a JT 14 tooth for the XRR instead. Out of curiosity, I tried to mount it up and low and behold it fit, though I did have to tap it on. I was so pleased I went right back in and ordered a 15 tooth as well. When my XRL was stolen, it had over 14k miles on it and no signs of countershaft wear. I always greased the splines each time I changed my oil, using red gun grease in a syringe type applicator. The stuff is high temp and high pressure, but I can't remember the name off the top of my head. White syringe about 5/8" diameter with a red bullseye on the label.

-Joe

[SpudRider]

Today I mounted a new Dunlop, D606 rear tire. At that time I seized the opportunity to remove my XR650R countershaft sprocket to examine both the sprocket itself, and the countershaft splines. Here is a photograph of the "front" side of my XRR sprocket, as mounted (reversed) on my XR650L, with 1,200 miles of wear.

Here is the "back" side of my XRR sprocket, as mounted (reversed) on my XR650L, with 1,200 miles of wear. My XRL sprocket actually exhibited more wear on the back side than this XRR sprocket, so I am very pleased.

Here is a photo of my countershaft splines after using the XRR sprocket for 1,200 miles.

Here is a comparison photograph of the countershaft splines at 10,000 miles, just before I installed the XRR sprocket.

My rear sprocket is in excellent condition; I did not note any significant wear. My drive chain is also in excellent condition. My XRR countershaft sprocket came off easily by hand, and reinstalled easily, by hand. The sprocket retainer is in excellent condition, and mounts securely to the sprocket and countershaft. So far, I am very pleased with my XR650R countershaft sprocket, and I intend to continue using the XRR CS sprocket.

Spud ?

[arranb]

is it very hard to replace the splined shaft? mine is very bad. or should i just let it go until it completely strips out? i wish the guy who had my bike before me did this kind of research......oh well. 03 xr650l thanks

[SpudRider]

is it very hard to replace the splined shaft? mine is very bad. or should i just let it go until it completely strips out? i wish the guy who had my bike before me did this kind of research......oh well. 03 xr650l thanks

Yes, it is difficult to replace the countershaft; you need to remove the engine, and split the crankcase. ?

If you don't have the time, knowledge, or money to replace the countershaft, I suggest you try an XRR counteshaft sprocket, and see if it works.

Spud ?

Edited April 17, 2011 by SpudRider

[craftsman13]

i bought a XRR Renthal 15t countershaft sprocket yesterday and i couldn't get the retaining clip on. what do you guys think about using a cir clip or snap ring? i know its not a good idea with the XRL sprockets because there is a lot of movement there, but with the wider sprocket it shouldn't be an issue right?

[SpudRider]

i bought a XRR Renthal 15t countershaft sprocket yesterday and i couldn't get the retaining clip on. what do you guys think about using a cir clip or snap ring? i know its not a good idea with the XRL sprockets because there is a lot of movement there, but with the wider sprocket it shouldn't be an issue right?

If you search this forum I believe you will find at least one, or several XR650L owners who have employed a circlip with the XRR countershaft sprocket. I don't know if these riders encountered problems later, but they never reported any problems. ?

When I installed my PBI, XRR countershaft sprocket I needed to tap it with a hammer quite a bit to get the retaining plate to install. However, after riding with my PBI, XRR sprocket for 1,200 miles, it now easily removes, and easily installs by hand. ? Therefore, rather than use a circlip, I would either get another XRR sprocket that installs more easily, or I would lightly tap the Renthal sprocket into place with a hammer, and install the retaining plate. ?

Spud

[BackonBike]

OK, I'm sold on getting an XR650R sprocket and flipping it around to save my countershaft splines . . . but I'm a newbie here.

I want to order an OEM 14t XR650R sprocket, along with a Moose Racing 15t XR65R sprocket.

Right now, I have a 15t front sprocket with a 45t rear sprocket.

I like 15-45 ok for highway, freeway, but it seems a bit fast for the trails. Some other posts seem to indicate easy enough freeway top speeds with a 14-45 setup, some so I'm keen to try that out.

And now, finally, the question: Do I need to get a new chain and a new rear sprocket if I want to change out to a new XR650R 14t front sprocket?

If yes, any recommendations? I look at all the possible chain ordering options, and my head spins.

Right now, my goal would be to be able to run with a 14t on the front, 45t on the rear . . . and see how that works for me on the trail and highway. If it's great, then I might never mess around with it again. If I miss the 15t for highway, then I imagine I'd want to switch them out depending on what I'm riding.

Oh, one more thing: Since the only experience I have with chains is repairing broken bicycle chains (twice), I'd prefer a complete chain of the correct length from the point of purchase. Unless that's just stupid, too.

The bike is a '94 XR650L with 6,000 miles, and since the PO sent me off with an old rear sprocket and broken chain in a cardboard box, I'm assuming that it's not the originals. What's on the bike seems in pretty good shape to me (but I'm a newbie) and a local bike mechanic didn't mention the chain at all after he mounted new tubes and tires for me last fall.

Thanks!

--Chris

[SpudRider]

OK, I'm sold on getting an XR650R sprocket and flipping it around to save my countershaft splines . . . but I'm a newbie here...

Welcome! ?

...And now, finally, the question: Do I need to get a new chain and a new rear sprocket if I want to change out to a new XR650R 14t front sprocket?...

You can experiment with the XRR CS sprockets without installing either a new drive chain, or a new rear sprocket. ?

...Right now, my goal would be to be able to run with a 14t on the front, 45t on the rear . . . and see how that works for me on the trail and highway. If it's great, then I might never mess around with it again. If I miss the 15t for highway, then I imagine I'd want to switch them out depending on what I'm riding...

That sounds like an excellent plan.

Spud

[craftsman13]

i tried tapping it on and it was bottomed out, i think the sprocket is just to big maybe i will try another one. i'm going to search the forum and see if anyone is using a c-clip.

[XR650L_Dave]

You could hit the sprocket splines with a dremel and chamfer them just a tiny bit more, if that's the part that is hanging up.

Dave

[arranb]

which way do you mount the sprocket? thanks.

[XR650L_Dave]

The XR650R sprocket goes onto the XR650L backwards, raised-face towards the engine, flat-side out towards your boot.

Dave