Bicycle Mechanics - Adapter claw on Cross Check (or do I need a new derailleur?)

Hi,

I am currently in the process of building a Cross Check using the drivetrain from an old bike. So far everything works as expected except the rear derailleur. It is some sort of old Shimano "Altus" which comes with an adaptor claw (which I believe cannot be removed from the derailleur) that I use with Dura-Ace 9 speed barcons in friction mode and a 8 speed 11-28 SRAM cassette.

I've attached pictures of the derailleur (please don't mind the dirty chain).

First problem: when I shift on the smallest cog, the chain rubs on the adaptor claw's bolt. I've read in another thread that this could be solved by adding a washer each side of the hub. It should be easy because the Cross Check has 132,5 mm spacing, but it would make my second problem even worse.

Second problem: the dropouts are thicker than on my previous frame, so the derailleur is further right from the cassette on the Cross Check (by a millimetre or two). Even by adjusting the limit screws, the derailleur cannot engage the chain in the first cog (it could on the old frame because the metal on the dropouts was thin enough).

My question is: is there a way to mount the derailleur directly on the frame's derailleur hanger? I think it would solve both my problems at once. However, I think my derailleur is riveted or similarly attached to the claw adaptor (i.e. without a screw).

Or should I buy a new derailleur? In that case, is it better to find one on eBay/craigslist or at my LBS? Should I use a mountain or road derailleur (I have a standard double in the front)? Weight is not an issue, but reliability is.

Thank you, I'll post pictures of the build once it is complete.

JE

From your pix it does not look like the hanger is designed to be removable, though it could be but you would still be left sans the 10Mx1.0 threaded bolt
that is standard RD mount. Best bet is a new RD, which for an 8-9spd should not be very expensive. RD come short, mid and long cage and the long
cage (on road RD) is still shorter than an ATB cage. For a double CW within the 16T or less range between CW sizes and an 11-28 a mid or long
road cage would do. ATB length cage would work also but has more chain wrap than you imply. Most road RD hit their limit at 27-28T on the cassette
but the appropriate B screw adjust should handle this. For pix and prices on bunches of new RD look at www.aebike.com I suggest this site as they
have a wide variety of RD in multiple price lines from $20 on up from several manufacturers and not just the latest 10-11 spd stuff. It is a place to start.

The built-in rear derailleur hanger on the Cross Check is permanently attached. Get any new rear derailleur intended for a bolt-on mount. What you have cannot be modified and, frankly, wasn't very good even when new.

I recently tried to separate an old derailleur from it's adapter claw.

I gave up.

With a lot of work, you CAN separate that derailleur from the claw. But it's not worth it. As HillRider said, it wasn't a good derailleur to begin with.

Thanks for the advices and for the link. I will look for a new derailleur. As a temporary workaround I found another old derailleur in my garage that can be bolted on the derailleur hanger (I don't think it is better but at least it works for now).