I have an 88 Trek 1200 12 speed with a six cog freewheel (I think). My freewheel has left me scratching my head. It leaves me with some questions:
1. What kind of freewheel is this and how do I remove it? It does not have any visible splines for accepting any sort of tool that I can see. I have read that some uniglide freewheels can only be removed with two chain whips because the first cog has to be unscrewed off. Is this one of those?
2. Does this freewheel look bad enough to need replacement? My chain is noisy and skippy on it, but the chain is fried (very stretched).
3. I have indexed DT shifters (Shimano 105). What do I need for a chain?

I will try the add a picture function in hopes that it works for me. If not, I will add a backup link to a picture of the freewheel in Photobucket.

Thanks in advance.



Image2.jpg Photo by racoonbeast | Photobucket

That is a freewheel rather than cassette. There are splines - may be too deep for you to see. I believe Park FR-1 will work. I Would just go ahead and replace chain and freewheel if the chain is quite stretched. Same tool should fit on the replacement freewheel for future use.

I can't see the splines well enough. And it's hard to tell cog wear by eye.

If it's noisy & skippy, then it sounds more like an adjustment problem, although it can also be worn. You can try a new chain. If you are lucky, then the freewheel is not worn too much and the new chain will work. But you need to have it adjusted properly so you can tell if skipping is due to worn freewheel and not to bad adjustment.

As stated by others you'll need Park FR-1 to remove the freewheel . as far as the cogs goes they look fine , but if after replace the chain and adjustment and it still jump then replace the freewheel too .

Thanks guys. I guess I have been reading too much into this. I know I must sound kind of pathetic, but I have never changed a chain on a bike before. What do I have to do to "adjust" it? I have a good Park tool chain breaking tool. I have got that far. I have not ordered the chain yet because I don't know what to get. Hyperglide or Uniglide compatible or any old six speed chain? Thanks again for all of your help so far. This has been driving me nuts trying to research and ID that freewheel and figure out how to get it off.

To get the FW off, you need the Park tool and a wrench that opens to 1". A 12" crescent should work if you don't have a 1" .
Suggest you install the tool, reinstall the skewer to help hold remover in place and keep it lined up straight. Snug it up then back it off a turn. Loosen FW slightly, back off skewer 1 more turn, repeat. By then, the FW should be able to be spun off by hand.

Get a 6-8 speed HG compatible chain. I'd stay away from the X-mart chains, but otherwise most anything should be fine.
Set chain length-
Loop over the largest Ring & cog without running through the RDER.
Allow at least 1" (2 links) but less than 2" (4 links) excess. It has to be in 1" increments, since you have an inner & outer link.
The chain has NOTHING to do with your shifters. DER's do!

I find the easiest way to remove freewheels is to clamp the tool in a vise, put the wheel on it freewheel down, and use the wheel as leverage. Much easier than removing casettes.
Those freewheel cogs were steel, and it took a lot to wear them out, so I would bet you will be ok with just a new chain.

Yes to clamping the tool in a vise being easier, but only if you have a strong, securely mounted vice.

No to betting on the cogs not being worn - if the chain is as worn as the OP says and the small cog was ridden much it likely will skip with a new chain. But there's no need to bet or guess. Replace the chain and then if you get skipping replace the freewheel.

It looks to my eye that the teeth are well worn, need replacement. It's a freewheel. Try the park FR-1 (1.2) tool first for fit. But some of the knock off freewheels (other then a Shimano) that look like a Shimano take a FR-5. So the fit is the check. Use a 7.1mm or wider (up to 7.8mm) chain. SRAM PC 830(1) works well. Andy.

Thanks a million guys. A couple of questions (I have never done anything on a bike more complicated than raising and lowering the seat and want to learn):

1. Bill K advises to leave a couple of extra links on the chain. I have not read about this anywhere. Everything I see says count the links on the old chain and size the new one to that number of links. Do I leave two extra links?
2. Several answers tell me that after I put the new chain on it needs "adjustment". What do I do to "adjust it"?.

Sorry to be so ignorant, but you guys are teaching me a lot that I need to learn. Thanks again.

You need to use better sources - no idea how you found only ones that said to size according to the old chain. Any site or person that says to size the new chain according to the old one is incompetent.

The best sources for repair procedures are sheldonbrown.com and parktool.com/blog. If you had clicked on "New posters - please READ THIS" at the top of this subforum those sources would have been mentioned in the first entry, and if you had Googled size bike chain or bike chain length or install bike chain those two are the first results. Videos and forum entries should be used primarily as backup to see the procedure or get a slightly different perspective.

There are different ways to size a chain, but the most common is that mentioned above. A FULL link is an inner and outer link, and one full link is the minimum to add.

There is no "adjustment" to a chain once installed- more poor info. Technically it should not be necessary to adjust derailleurs if they were OK before, but it's good practice to check anyway.

p.s. I'd love to know which sites gave the poor advice you cited.

I started off by goggling how to change chain and got lots of hits. The ones that I read, and I have read a number of them, left me with the impression that the most accurate way to size a chain was to count the number of links in the old one, and keep the same number of links in the new one. I don't remember who or where these were. But there was more than a few. I have just read the Park Tool procedure for sizing a chain, and I think that I am starting to understand this procedure. I am still befuddled as to why just counting the links in the old one would not give you the correct size on the new one. I understand that matching the overall length to overall length would not work because the problem with my old one is that it is stretched (there are a few people out there recommending this as well). But, if two links equal an inch on a new chain, it seems natural that the same number of links on an old one would match the same number of links on a new one. I am not doubting the integrity of the suggest procedure, recommended both from members here and Park Tool. I am just trying to understand it. Is it because all links are not exactly half and inch and there could be differences between different manufacturers?

The reason is very simple. You have no assurance that the old chain is properly sized. Someone could have installed a chain of the wrong length or just removed a bad link. It's exactly the same as replacing a tube, as sometimes people put in whatever they have instead of the right size, so one always goes by the tire size rather than the tube that is in there.

As mentioned, you have no assurance your current chain is sized correctly. It should be, but it may have been replaced at one time by someone that didn't have a chain tool and just put on the full length, new chain.
OTOH, if your current chain is working WELL, you wouldn't really do any harm by matching the current number of links.
It's just that you post in a MECHANICS Forum and they are trying to tell you how to do it the CORRECT way.
Size it right this time and next time you CAN just count the links.

That said, some RDER's have a lot more take up capacity then others and a slightly longer chain won't be a problem.
Since yours is a Road bike, you probably don't have as much leeway as you would with a "mountain" RDER.

What you are not thinking about is that it probably takes not much time at all to fit a new chain onto the bike. It certainly takes less time thn multiple posts trying to decide what's wrong with counting the links on the old chain!

Thank you all who offered helpful advise. When trying to learn about something it is as important to know "why" something is the way it is, as it is to know "what" needs to be done. I understand the situation now and have learned much. It was kind of you to take the time to explain this to a newbie.

Go to this website, and on the right hand side it will give you a list of various services. Choose "Chain service" and then read up. Park Tool help website is your friend.

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