GT i-drives

Being a bit a of a GT fan, I've often wondered about getting a more modern i-drive bike. My problem is that my GT knowledge doesn't really extend beyond the 90's (other things took over my interests - like most people). I've had a look for info on the history of the i-drive model range, but I haven't really found anything that explains how the frame developed and what the difference is between the various incarnations.

Anyone know of a good source of info, or care to give a potted history of the breed?

A users explanation of i-drive: http://www.youtube.com/watch?v=R4AVEiTW ... re=related

Seems that the design helps push the rear wheel in to the ground via the use of the linkages and a kind of leaf spring. Seems to be a few reviews on the web on the various models. I'm sure some of the RB i-drive fans can give you a users guide to the models. Looks a good design though, certainly different to what other manufacturers offer.

Bit more info around the yr 2004 on this timeline overview of the company: http://sidewaysandfallover.blogspot.com ... ycles.html

thanks for the links - I've seen the sideways and falling over blog before and there's some good info in it. I was more interested in the history of the frame / i-drive system development from the XCR1000 models through to the later increments of the i-drive models.

cheers

not sure how they developed etc. etc.
but i do know the original bb assembly was heavy and they lightened it up for the newer designed ones (idc or whatever theyre called)

Ah memory lane, I had one of these in 1999, an xcr 2000

The main pivot bearing/bb shell was a lovely bit of engineering, and the i drive really did work. It just digs in and gives you traction, whilst still being soft and supple. It feels a little less active standing up though, but it still makes for a good all day trail bike.
It had a nice set of QR20's up front too so it was fairly weighty.

I've got an 09 mongoose canaan, which uses a licensed copy of the I drive and it works in almost exactly the same way, although its a lot more compact now (though less cool looking).

I've got an I Drive 5 from around 2005

TBH I was a little sceptical at first but after taking it to quite a few trail centres it's a design that really works.

i had the very first "every trail faster" demo one from my mates bike
shop waybackwhen and destroyed the i-drive bearings in about 2 weeks
of thrashing in our gritty winter
it went back to have an up-graded set fitted and no more probs

had 3 over the years and in my opinion the 2004 marathon/ race
ones are the best , but not ridden the newer ones

great things , and do work really well as a singlespeed
dogbone bushes are usually the first and generally only bits
to give bother easy sorted tho
on the 2000 + ones the seat mast changes relative to the models
so get to know what your looking at with that as a start point
oh and a fox air can shock does wonders for the ride

I loved the ride of my various i-drives. They were all the original design with the large eccentric with the bb mounted inside. The only real difference between the XCR models and the later i-drive 1.0, 2.0 etc were changes to the seat pillar and increased machining on the rear triangle and eccentric unit. This made the frames lighter, but meant that the spare parts were not all backwards compatible (particularly if the frame was USA made as opposed to Taiwanese made). For reference BETD engineering still make spares for most GT full sus frames including the i-drives, so you can purchase with confidence. Some time around 2005 the design changed considerably with the eccentric getting much smaller and the bb becoming separate.

I don't know much about the frames once the eccentric unit and BB were mounted separately, but I expect someone else will be along to fill you in shortly!

Yeti have just released details of a similar design using an eccentric mounted linkage, so there must be something in it.

thanks for the comments guys, this is all useful stuff to select / justify my next possible acquistion