GT Performer, Bottom Bracket Bolt.

[Haro Fan]

Here are a few questions for the GT experts. If anyone can help, I'd appreciate it.

Does anyone know what the purpose of this bolt is, mounted on the underside of the bottom bracket shell on a GT Performer? Is is it a cable guide for a brake mounted on the underside of the chain stays or for something else? It doesn't seem to be there on all of them.
 http://cgi.ebay.ie/ws/eBayISAPI.dll?VISuperSize&item=120649807214

Also, is the GT Performer and GT Pro Performer based on the same frame, only different spec components for each model?

Why do some GT frames have 4130 stamped into the top tube butt while others don't have this stamp. Did the Performer get built from different types of tubing? Thanks.

Liam.

[HEYWOOD BMX]

  Does look to be a cable adjuster mount for a brake mounted under the chainstays.

http://cgi.ebay.co.uk/Old-School-Chrome-1987-GT-Performer-BMX-Frame_W0QQitemZ120649807214QQcategoryZ64644QQcmdZViewItemQQ_trksidZp5197.m7QQ_trkparmsZalgo%3DLVI%26itu%3DUCI%26otn%3D3%26po%3DLVI%26ps%3D63%26clkid%3D5158721694918449165

[Haro Fan]

Thanks for all the answers. It's hard to get a handle on all the different versions of the Performer. I have plans now to attempt a build of a Martin Aparijo 86 GT World Tour Performer replica.

Along with the Haro Master, I think the Pro Performer is up there as one of the classic old school freestyle bikes. I just didn't realise how hard it is to track down these OS bikes. Thanks.

Liam.

[Haro Fan]

You don't fancy selling one of the 86's, do you?

Can you tell me if the Performer frame in the picture above is a US-built frame or one from Taiwan? Are the Taiwanese ones crap? Thanks.

Liam.

[Haro Fan]

Thanks Steve. I'll have to save a bit before I can make an offer for your Performer!

I had a look over on the BMXMuseum Forum and they have a lot of great info on the serials on GTs. Just as you say, the serial on the BB means a Taiwanese frame. That begs the question, are the Taiwanese frames built to the same standard as the American ones? I would guess that the American frames are the most desirable but are the Taiwanese frames up there with them when it comes to actual build quality? Thanks for any input on this, Steve.

Liam. 

[ozone]

from 87 there was no such thing as a pro performer with a single bend in the downtube.

There was a standard single-bend performer available from right up until 1989.  Must have been the budget bike in the range...

On page 12  http://www.ajkbikes.com/downloads/catalogs/1989%20GT%20Catalog.pdf