1989 Trimble Inverse-4


Karma King
Still a little tweaking to do, but it's up and fully rideable now, ready for the weekend - finally!

Fitting the Magura on the rear U-Brake mounts was an absolute pig, and required a little bit of 'experimentation' - but it all works... :)

Forks are RS1 crown with Mag20 lowers, modified with reverse mounted brakes as per the wonderful Deb Murrell Formula 1 bikes.

Build-wise it has the RooBar bar/stem combo, XT headset, BB, front mech and thumbies.

Brakes are first generation HydroStops, with a mishmash of original and slightly later mounts [aaaarghhhhh!]

Onza grips [NOS, but split as soon as I put them on of course].

Middleburn RS1 cranks, with Middleburn outer and Venhill middle & inner rings, and some spare SRP crank and chainring bolts I had lying around.

Wheels are Ringlé Bubbas front and rear, with WTB Speedmaster rims.

Post is American Classic, saddle an Avocet Racing 1, and the saddle and wheel QRs are a set of Ringlé.

Tyres are whatever I had to hand just to test things out, and are not mounted correctly at present in terms of logo alignment but that's for another day now.

Pedals of course are the ones I have on all bikes - Onza H.O - chain a lovely HG93, and the tubes are probably Vittoria but I honestly can't recall now.


  • 09.JPG
    452.2 KB · Views: 885
  • 08.JPG
    597 KB · Views: 882
  • 07.JPG
    552.2 KB · Views: 882
  • 06.JPG
    667.3 KB · Views: 882
  • 05.JPG
    520.9 KB · Views: 882
  • 04.JPG
    700.4 KB · Views: 881
  • 03.JPG
    694.4 KB · Views: 883
  • 02.JPG
    687 KB · Views: 884

mk one

Old School GrandMaster
Retrobike Rider
BoTM Winner
Gold Trader
Kona Fan
:cool: :D some nice parts on there, that saddle :cool:


Retro Guru
Love this build. It's not often you can put a sticker where your have the Oakley one! Like the roadie 105 rear mech too.

Where did you get your cable outers from?

I want to trim your seat QR bolt :)