Team Marin Rockstar 750g Spinner Forks - A tale of woe...help needed

[trezize]

A little while ago I picked up a 95' Team Marin. It came with an assortment of non original parts and a fooked, very heavy suspension fork. https://www.retrobike.co.uk/threads/marin-team-issue-info-and-suggestions.490538/

I have set about sourcing a replacement rigid fork as I wanted to lighten the bike up and use it for some up-coming touring.

I was able to locate a Marin 750g Spinner fork. It fit perfectly in terms of axel to crown and the rake was exactly what I wanted geometry wise the paint was also good, the colour was a nice accent. The only issue, the steerer was too long.



Enter the local bike shop; they attempted to shorten the steerer and messed it up, totally cooking the thread. They have been very good after the mistake and will help fund a replacement fork.



So I am now asking for the following help please:

1. Is there any possibility of salvaging these forks? The steerer will be too short if the affected thread is cut off. Has anyone had any success with cutting and welding? Is this an economical or even a possibility? Any other solutions?

2. How rare are these forks. I have seen lots of the standard Rockstar forks but the 750g version seem to be rare. Did the Team Marin and other higher end Marin frames come with these forks as standard if a rigid fork was optioned?

3. Does anyone have a similar fork available? I am not necessarily precious about it being Marin branded, it was more the shape and weight I am after. My head tube length is 120mm.

4. The bike shop said that their Park Tool cutting die wasn't suitable for CRO-MO steel? Is this possible?

Thanks for all your help. I hope my disappointment can be the source for some interesting discussion.

Cheers

 

[Tootyred]

What a mess! Sorry to hear that. Looks like they tried to cut with not enough lube and in one go without backing off to relieve the thread of its swarf (chip).

Those dies will cut steel no problem.....

As for repair, its probably not worth paying to cut extend the steerer. £50 quid should buy you a great pair of 750g forks in the correct size for you frame. £25 for a manky respray pair..imho.

I would sell them on to somebody with a smaller headtube and ask the shop to "fork out" for a replacement.

Stick up a wanted advert on here.

The 750g and 730g forks came on the higher end models. Although, its a bit of a joke as they were only 750g on a 15.5" small frame! By 20.5" they were a kilo.

I think @Oldfellatn3 was selling a really good pair of shogun triple butted forks very cheap. If the steerer is long enough, they would be magic. Been very tempted by them myself, but too short for my lankyness!

O

Reduced Post in thread 'Shogun 1 -1/8" triple butted Cro Mo forks / Tange Seiki falcon FL270c headset.'

May 18, 2025

Forks £33 posted uk

• Oldfellatn3

 

[bikeworkshop]

The truth is that the park tool cutting die is really for cleaning up damaged threads, and maybe running a couple of extra turns of thread down the steerer.

Actually threading the fork is a job best done by engineers.

It looks like the mechanic was out of his depth here.
It is possible to cut an amount of clean thread with a shop tool, but it's very difficult and very slow.

I've done a few, it was popular in the days of Threaded headsets
and now would send any fork to our near neighbours Argos who have engineering tools.

 

[Tootyred]

^ totally.

You would have thought they might have stopped when they realised it was going horribly wrong all the same!.

Its not funny really....cutting threads is slow. Half turn, back chip, half turn, back chip. Its just a lack of experience.

Engineering shops just wizz them up....takes longer to make the tea!

 

[bikeworkshop]

There's quite a bit of skill to it, adjusting the die and all that half/ quarter business, but ultimately the hand- held tool isn't really up to the job.
The steerer is often hard enough to trash these things in a dozen turns even if you are clearing the swarf correctly.

That's probably the source of the "cro-mo?no-go" idea.

I suspect the mechanic thought the tool would do the job, and didn't have a plan for if it wasn't going well.

Cognitive lock, I believe it's called.

If you don't know what's right, it's hard to know when it's wrong.

 

[trezize]

In all fairness the shop has been very good with admitting fault.

The mechanic admitted his inexperience with this particular job and said that although it's straight forward in theory, in practice it's something that requires a fair amount of experience and admitted a degree of hubris on his part.

I can see that it is one of those bike build jobs that might not be done very often so it's difficult for a younger mech to get experience with it.

If the replacement fork suggest by @Tootyred has a steerer of 160mm, my frame has a head tube of 120mm and I am working with a Ritchey Logic headset with a stack of 38mm plus a front brake cable hanger. Will these forks be suitable?

Thanks for the help and feedback guys.

 

[bikeworkshop]

Aluminium handsets are usually more than 2-3mm thick.
Steel ones are thinner, so this fork is workable.
But after decades of dealing with Threaded forks, I must say I would never fit a brake hanger within the headset assembly - those delicate threads were never designed for this.
Use a stem mounted or fork mounted cable hanger, so all the stress is taken by a piece designed to do exactly that.

You don't want to be throwing another fork away!

 

[bikeworkshop]

I just remembered though that when threads were common, and a section trashed by a loose locknut, (or brake hanger) i used to run some braze over the damaged section and recut the threads.
This is a little more extensive, but it's worth a thought.

 

[Tootyred]

If your head tube is 120mm plus your stack of 38mm thats 158mm. In theory you may need to cut off a few mm or add a spare headset washer!

Obviously can't comment on rake, but you probably wont notice much difference in the real world even if they are a bit different.

 

[Tootyred]

Im with @bikeworkshop put the hanger on the fork crown or on the stem....dont jam it into the headset stack. Your leverering the headset threads every time you put the brake on.