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Rick1956
10-26-2021, 11:37 AM
Hi all,

While reassembling things on my wife's 85 110 recently I ran into a strange fitment issue. Try as I might, I could not get the chain to feed around the front sprocket properly. It should have been easy! I was using the '85 chain guide of course, which has a bend in it that fits into the case. Well, under perfect conditions it does. The guide is made from some pretty soft steel if you ask me, and the end of it is pretty easily 'reshaped' by chain mishap. Because of that I have no real way to tell if the contour is still the way it's supposed to be. I have an '84 nearby but I didn't want to disassemble that guy for a comparison looksee. I was feeling lazy.

After fighting it for a while, trying to figure out what the chain was binding against, I wondered if the chain itself might be contributing to the issue. It seemed unlikely, being both of the chains are #428 like they're supposed to be. Then I compared them:

268454


Well, the new chain (JT Sprockets HDR) is considerably beefier than the wannabe that I replaced, so that was definitely staying put. In resignation I chose to leave the guide completely out and move on. That's when I remembered I had one from an '82 in a box somewhere. I dug it out hoping to compare shapes, but found it do be different than the '85 part. I held it in place and found it to be exactly what I needed. It popped right in like it was made for it. (Well, technically I guess it was).

The '85 uses this version (#17 below)

268455


While the '82 uses this version (#8 below):

268456


While there is no 'case guard' benefit extending into the case like there was originally, it fills the opening to keep crap out at least.

Is it typical for the newer chain guide to be a 'barely fit' type of part? What do most of you do with these guys?

DAM shop
10-26-2021, 10:15 PM
Good observation Rick. Is the new chain a O ring chain perhaps? We’ve had our share of pain in the arse chain feeding for sure. One easy way to feed a chain is to leave the old in place and hook into the new and pull it through.

While reassembling things on my wife's 85 110 recently I ran into a strange fitment issue. Try as I might, I could not get the chain to feed around the front sprocket properly. It should have been easy! I was using the '85 chain guide of course, which has a bend in it that fits into the case. Well, under perfect conditions it does. The guide is made from some pretty soft steel if you ask me, and the end of it is pretty easily 'reshaped' by chain mishap. Because of that I have no real way to tell if the contour is still the way it's supposed to be. I have an '84 nearby but I didn't want to disassemble that guy for a comparison looksee. I was feeling lazy.

After fighting it for a while, trying to figure out what the chain was binding against, I wondered if the chain itself might be contributing to the issue. It seemed unlikely, being both of the chains are #428 like they're supposed to be. Then I compared them:

268454


Well, the new chain (JT Sprockets HDR) is considerably beefier than the wannabe that I replaced, so that was definitely staying put. In resignation I chose to leave the guide completely out and move on. That's when I remembered I had one from an '82 in a box somewhere. I dug it out hoping to compare shapes, but found it do be different than the '85 part. I held it in place and found it to be exactly what I needed. It popped right in like it was made for it. (Well, technically I guess it was).

The '85 uses this version (#17 below)

268455


While the '82 uses this version (#8 below):

268456


While there is no 'case guard' benefit extending into the case like there was originally, it fills the opening to keep crap out at least.

Is it typical for the newer chain guide to be a 'barely fit' type of part? What do most of you do with these guys?[/QUOTE]

Rick1956
10-26-2021, 11:43 PM
Nope, it's' not an o-ring chain. I would hate feeding one of those too. This one was easy to feed (once I removed the obstruction) using my screwdriver 'pushing' technique (patent pending).