What rear spacing is a Marin Bobcat trail?

[Ugo51]

Hi guys,
I recently purchased a Bobcat Trail frame, with the intention of restoring it.
Aside from superficial rust and a dent in the top tube (not advertised in the ad...), it seems fine.
But the rear spacing is 112mm...
I don't know much about bikes, but that doesn't sound right :facepalm:
I was expecting 130mm.
Is there an explanation to this, or do you reckon the chainstays have been bent?

Cheers

 

[marc two tone]

Re:

Bobcat came along in 1993, should be 135mm.

Sounds like it's been jumped on, whilst laid flat.

Edit, soz 7speed, maybe 130mm

 

[Ugo51]

Damn.
I should have checked when I got it, I could have avoided 1hr of sanding...

I wonder how they did it?? I can't believe it was an accident

 

[marc two tone]

Re:

Personally I'd have a look at the tubes and weld points for trauma.
If it seems ok, tease the stays apart and shove a wheel or loose hub in.
Listed for that creaky click sound, the less the better. You may get away with
The whole situation if the metal can take it.

 

[2manyoranges]

Re:

well, steel can readily be retracked. Which belies its technical-sounding character. Even in a specialist's workshop it means car jacks, long scaffolding poles, and lots of welly.

Alloy is something else. You are not supposed to re-track heat-treated aluminium without it going through heat treating again. Only I have. And it's been fine. And about the same extent to which you have to. Yes, the frame almost certainly was 135. I retracked a Cannondale which had the same problem, using a car jack inside the stays to slowly, slowly bend the rear triangle back into shape. Was fine. And ran for years without any problem. That's my experience. There was no buckling on the rear triangle, and I was extremely cautious. But you need to carefully evaluate whether it can be done to yours without compromising the frame. As MTT says - check for points of trauma, and if you can find any, the frame is unduly compromised.

 

[Ugo51]

Some good news. First of all, I got my money back for the frame, as clearly it was not "as advertised".
Having nothing to lose, I tried to open up the chainstays and I have to say, I was surprisingly successful.
I have no tools to do the job, so I did it by brute strength (which I have in very limited supply, but apparently enough for the job).
I used some fixed reference points to establish it was the drive-side chainstay that had to be re-bent, and so I did. The dropouts were also bent, but those were easy to put back in place, using an adjustable wrench.

It's now 130mm, and it feels right. I know you guys said it was supposed to be 135, but it's centered and 130mm takes a 7-speed hub, so that's OK for me.
Of course, there might still be some minor misalignment. I don't even have a work bench, so the job will never be perfect.
Now the plan, before stripping it of the paint and re-painting it, would be to buy and fit the components to feel how it rides.

 

[marc two tone]

Re:

Great news. Another marin out there.

I agree, just ride the bar-steward now.
Very rare a steel marin fails. No matter rusty or tortured.

Do you have the whole machine, wheels n all?

 

[Ugo51]

I don't have anything but the brake calipers.
I will need to do some shopping now!
Which I'll need some help with. But I'll open a new thread for that

 

[hamster]

Re: Re:

well, steel can readily be retracked. Which belies its technical-sounding character. Even in a specialist's workshop it means car jacks, long scaffolding poles, and lots of welly.

Sounds like you have never done it.

You need a 65mmx50mm sort of dimensions piece of timber, about 2m long. Lay the frame on the floor, thread the timber into the rear triangle with the tip just beyond the seat tube. Prop the other end. Then bounce gently, measure, retry. Then do the other side, etc.

Take it gently, at the end check the dropouts are parallel - tweak by clamping in the jaws of an adjustable spanner.