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crank sprocket XR 200

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I am posting this since I have seen a couple people ask about changing the crank sprocket for the camchain. It can be done without splitting the case or even with the engine in the frame. It takes a little planning and some tools/ pullers you may or may not have but should be readily available for the most part. Your local NAPA or other Auto Parts store may rent you the puller.

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8475.jpg[/img]"]IMG_8475.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8476.jpg[/img]"]IMG_8476.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8477.jpg[/img]"]IMG_8477.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8478.jpg[/img]"]IMG_8478.jpg

all of that should be self explanatory.

I grind the inside of the old sprocket just enough so it slips off and on easily and use it as a spacer to help me press the new one on.

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8479.jpg[/img]"]IMG_8479.jpg

I use a hardened automotive stud 8mm x 1.25 thread pitch that screws into the crank, a hardened nut, washers, socket, spacers, whatever to use as a press. I also mock everything up ahead of time to make sure I have the right spacers, washers, etc. to be able to press the sprocket all the way on...plan ahead because you have to be have everything ready and work fast. I heat the gear up in the oven 350 degrees or so until nice and hot! Remember there is no keyway for the sprocket so 1 tooth aligns to the keyway for the flywheel. When you press things on this way there will be a little spin as the sprocket presses on. I usually start abought a half tooth or less forward and press away and it usually lines up. If you find yourself too far off it is easy enough to pull it off and do it again until you have it where you want it. You will have to heat it up again to try again.

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8482.jpg[/img]"]IMG_8482.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8483.jpg[/img]"]IMG_8483.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8484-1.jpg[/img]"]IMG_8484-1.jpg

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8485.jpg[/img]"]IMG_8485.jpg

I have done this a few times!

http://i413.photobucket.com/albums/pp215/basilfaulty/franken%20honda/IMG_8486.jpg[/img]"]IMG_8486.jpg

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Thanks, I was looking at this the other day but none of the pullers I had seemed to be able to get it to budge so I put it on the back burner. Question, is there a shoulder to stop the gear when you push it back on so that you can't go too far? Also, are you getting replacement gears from the dealer? Cost?

Thanks again

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Thanks, I was looking at this the other day but none of the pullers I had seemed to be able to get it to budge so I put it on the back burner. Question, is there a shoulder to stop the gear when you push it back on so that you can't go too far? Also, are you getting replacement gears from the dealer? Cost?

Thanks again

Yes, there is a shoulder on the crank to stop the sprocket. You have to make sure you push the sprocket on all the way. I use a dental style mirror to make sure I have it bottomed out. I buy the sprocket from Honda it is about $30. That puller is for power steering pump pulleys...the jaws are rounded out and almost surround the sprocket fully so it has a nice grab. I also use a 3/8 impact wrench to zip it off, I don't how much luck you would have by hand due to the crank spinning. I use the same impact to drive the new sprocket on. You have to make sure to mock it all up and have everything ready. Make sure the socket or pipe or whatever you use doesn't bottom out on the crank before the new sprocket bottoms out. I do it in 2 steps. I use a socket and washers to drive it most of the way on then I use the old sprocket, a socket and washers to finish it up. I couldn't find a stud long enough or with enough thread to do it in one step. I wouldn't try to do it with a threaded rod for fear of breakage or stripping threads. I use a hardened stud and hardened nuts. ALSO: make sure you put the new sprocket on the correct way 1 side has a shoulder on it and the other does not. If you put it on backwards the chain won't line up. Take a picture if you need to.

Edited by basilfaulty
added a thought

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Thanks for posting this. I'm getting ready to do it. And had not

come up with a good way to do it.

I was able to find a puller that looks like the one you used-hope it

works. I found it at auto parts store. O Reilly Parts, I got a Performance

Tool (brand name) Pulley Puller-part #W80653, it looks like the one you used.

Have not found the hardened stud yet. Went to the hardware store and they

were sold out of that stud.

Tom

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Thanks for posting this. It's very helpful. Now I can finally get rid of the one that's been on there for 15 years!

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I went online to lookup the part number for my 81 and every site has two different numbers. Any idea what's different between 14311-107-000 and 14311-958-000 ?

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I went online to lookup the part number for my 81 and every site has two different numbers. Any idea what's different between 14311-107-000 and 14311-958-000 ?

I looked it up on the site I use. It says 14311 958 000 replaces 14311 107 000 so it looks like it is just a superceded part #.

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I suggest marking the crank behind a sprocket tooth before pulling the old sprocket. Sighting the keyway to a sprocket tooth is difficult.

I would use a felt tip pen and mark behind the tooth closest to the keyway, then scribe the tip of the sprocket in the ink. Carefully observe how close to the tooth the scribe mark is, maybe take a pic. Then pull the sprocket and carefully examine how close the scribe mark is to the key centerline, now you have a reference for installing the new sprocket.

Great thread!

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good point Chuck. I have been sighting the base of the tooth against the whole key way as they are close to thesame width. Next one I do I will try the way you suggested. Once the weather breaks here I will have to finish up on the one I am building, then I will start on the next one with the x motor

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I've never replaced a sprocket out of concern that I couldn't achieve accurate alignment and would need to degree in the cam with a degee wheel and a vernier sprocket. I've been thinking about this and I think a rotor hub could be modified to become a tool to install the sprocket with more precision than visual alignment.

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I don't worry too much about getting it perfect. If anything I like to have the cam advanced a hair anyhow. I could really degree the cam in if I wanted to. I have a degree wheel, dial indicater, etc.

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I don't worry too much about getting it perfect. If anything I like to have the cam advanced a hair anyhow. I could really degree the cam in if I wanted to. I have a degree wheel, dial indicater, etc.

Like this from my 218 build?

DSCF1076.jpg

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Yep, thats the setup. I usually don't get that involved on a stock motor though. If I was building a 218 with a cam and everything I would probably dial it in. These engines in stock form are very forgiving. I tend to error on the side of retarded on the sprocket which in turn advances the cam, i would like to think no more than a degree or so as i usually have it spotted in pretty good. I check it and re-check a couple times with a straight edge against the keyway. If I have to I will pull it a try again if I don't like the alignment. The newer style crank sprockets (late model) have indexing marks built in to them so it is a little easier than the ealy ones. The bottom of the tooth is about the width of the key way so I line it up that way instead of trying to line up to the center of the tooth. I have done this with the motor in the bike as well, a little more difficult to align that way though.

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For those looking for a relatively cheap puller available online - I just picked up an Alltrade 648644 Kit from Amazon. It works great, with the jaws on the slimmer profile of the puller block. It's like it was made for the task...with the jaws in this configuration, there's not even a need to use the side thumbscrews to tighten the jaws. The block is the perfect width by itself.

It is Chinese made, for those that care - but the quality appears to be excellent.

Also, no need for an impact wrench in my case. I just used a large pipe wrench around the block of the puller to hold it steady and keep the crank from spinning while turning the puller bolt. Popped right off.

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Do you think you could press on a new crank bearing using the socket nut washer and stud method if the crank is out of the case?

Thanks

Mike

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Do you think you could press on a new crank bearing using the socket nut washer and stud method if the crank is out of the case?

Thanks

Mike

I don't know if the threads are strong enough for that, I would be afraid of pulling the threads on the crank. As it is I heat the sprocket up to press it on. if the crank was out of the motor a machine shop would probably press it on for you for like 10 or 15 bucks.

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Do you think you could press on a new crank bearing using the socket nut washer and stud method if the crank is out of the case?

Thanks

Mike

I don't know if that would work, IMO the 8mm bolt would break before enough force to push on a cold gear.

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I don't know if that would work, IMO the 8mm bolt would break before enough force to push on a cold gear.

thanks for the reply. I guess heating the bearing would be a bad idea. I will have to find a good machine shop.

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Just pressed on a new sprocket, and thought I would add a little info.

I was unable to make a pusher set-up with the studs I had so I used a bolt and just ran it into the crank. I didn't have much to lose, and my patience was at its limit, so I went for it....and, it was pretty uneventful.

I measured the thread on the bolt, and I had lots for the distance I needed to push, so I thought "haha, I'll get it in one shot, I'm such a genius" Wrong. The bolt bottomed out in the crank, and I sat there for about 20 seconds trying to figure out why it all stopped. Then I whipped the bolt out, put my old sprocket underneath and by golly she started moving again. Lined up first try. Total fluke, but I did follow the advice to start half a tooth ahead.

Here is my set-up fwiw. Used 1/2" impact. Plug socket was slightly longer than my deep sockets.

http://i1223.photobucket.com/albums/dd515/yellowhead72/PB060334.jpg

http://i1223.photobucket.com/albums/dd515/yellowhead72/PB060336.jpg

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