After the disastrous recall of every single one of its first model of derailleur (the SRAM ESP 900), SRAM boldly stuck with its dream, slightly redesigning the gear and sorting out the manufacturing process - and the 1996 SRAM ESP 9.0 and then the 1997 SRAM ESP9.0SL were the results.
The design of the 9.0SL includes all SRAM’s signature features; the one-to-one actuation, the steeply angled slant parallelogram, the lack of float in the guide pulley and the single sprung pivot design with the top pulley wheel almost concentric with the sprung pivot (all except one-to-one actuation and that 'almost' follow the basic design of the SunTour V GT).
When manufactured using ‘carbon composites’, with sealed bearing pulleys and an aluminium attachment bolt, the result was an extremely light and very capable gear. However, I personally still found it hard to believe that a plastic gear had the integrity of an aluminium design, and I found it hard to shake the unfair notion that this gear was a sophisticated toy.
I have come across 3 'standard' variants, and 2 special edition' variants, of the ESP 9.0SL. I think these can, possibly, be dated as follows:
- 1997 saw the first of the 'standard' variants with 'carbon' finish knuckles. It has a logo on its outer parallelogram plate which has a black oval shape with the words 'ESP 9.0SL' on it.
- The second 'standard' variant appeared in late 1997. It has a logo on its outer parallelogram plate which also has a black oval shape but sports the words 'SRAM 9.0SL'.
- 1999 (?) saw the third 'standard' variant. This has no black oval shape but has the words 'SRAM 9.0SL' in rather elegant script.
- The first 'special edition' model was the famous 'Betsy' design featuring the stars and stripes. It was issued in late 1997, to commemorate SRAM's 10th birthday. It features the late 1997 logo, but the oval shape is patriotic blue.
- The second 'special edition' model was the 'Woody' design featuring a wood-like finish. This was issued in 2000 to raise money for trail preservation. It features the last of the three logos.
This is an example of the third 'standard' variant - probably dating from around 1999.
- Derailleur brands: SRAM
- Categories: SRAM - ESP and all that
- Themes: Ultra-lightweight - touring/mountain bike
- Country: USA, manufactured in Taiwan
- Date of introduction: 1999?
- Date of this example: unknown
- Model no.: 600-714
- Weight: 192g
- Maximum cog: 32 teeth
- Total capacity: 33 teeth
- Pulley centre to centre: 85mm
- Index compatibility: 8 speed?
- Chain width: 3/32”
- Logic: top normal
- B pivot: unsprung
- P pivot: sprung
- Materials: carbon composite (plastic) knuckles and inner pulley cage plate, aluminium parallelogram plates and outer pulley cage plate.