Myles Posted November 10, 2005 Share Posted November 10, 2005 My rack was damaged in the Anglesey incident - I need a new one. The car is ex-Academy and i) my paperwork file states it had an 8% rack and ii)CC tech-help say that that was the regulation rack. It did do some grad work afterwards though (not sure about the regs, but wouldn't have thought anyone would bother changing the rack). Anyway, the rack does approximately 1.8ish turns lock-to-lock. CC say it *is* hard to identify which rack is which - but that 1.8ish turns is about right for the 8% and 1.65ish would be right for the 22%... ...however, a trawl through techtalk throws up a huge variation in figures - some reckon 1.8 turns is a 22% item, others agree that it *is* an 8% after all... Unhelpfully, by owners manual talks only of 'standard' (2.13) and 'race' (1.80) - this was printed in '01 - by which time the '8%' rack should have been standard... Can anyone shed any light on this? I had been offered first-refusal on a 96-spec rack - and this is reportedly around 2.25 turns... Although my rack is clearly damaged (by feel, I'd say the pinion was damaged), it would appear that I am still getting full deflection on it. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
paul jacobs Posted November 10, 2005 Share Posted November 10, 2005 When I had my last car I fitted a 22% rack, and that was just under 2 turns lock - lock, so I would say you have one of these 😬 Paul J. Hard work never killed anyone ........ but why take the chance! Link to comment Share on other sites More sharing options...
Myles Posted November 10, 2005 Author Share Posted November 10, 2005 There's very little difference between the figures CC gave me for the 8% and 22% versions though - 1.83ish vs. 1.65ish... - just under 1/4 of a turn (or 1/8th at each extreme)... How much trouble would it have been to stamp the bloody things with a simple code - or stick a coloured tag on as they do for ARBs etc... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Mike Bees Posted November 10, 2005 Share Posted November 10, 2005 At one time they were colour-coded. 8% were painted green and 22% were bare ali. There's a black one for sale on EBay here... Mike Link to comment Share on other sites More sharing options...
rgrigsby Posted November 10, 2005 Share Posted November 10, 2005 Hmm I think my 22% is black :) just to help out, it's only 2-3 years old though so that's probably why. Either way I'd go for one of those rather than an 8% but that's just my personal perference. Rob G www.SpeedySeven.com Link to comment Share on other sites More sharing options...
Myles Posted November 10, 2005 Author Share Posted November 10, 2005 Yeah, I don't think the colour-coding works these days, unfortunately. I've only driven a 22% rack once - and I was trying to keep (upto) 244bhp in a reasonably-straight line on a country road at the time (V7SLR just before he sold it) - I do remember commenting on the steering when I got back... I guess you'd get used to it, but mine was quite a handful over bumpy roads as it was... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Normans_Ghost Posted November 10, 2005 Share Posted November 10, 2005 Mines a 22%. I don't have too much trouble over bumpy roads (subject to tyres) but the steering is heavy. Mav's driven mine a few times ask him what he thought. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
rgrigsby Posted November 10, 2005 Share Posted November 10, 2005 Was it on ACB10's? if so that's the reason why, they're a nightmare on the road unless you are used to them! Rob G www.SpeedySeven.com Link to comment Share on other sites More sharing options...
Myles Posted November 10, 2005 Author Share Posted November 10, 2005 What? V7? No, it was on CR500s IIRC. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
rgrigsby Posted November 10, 2005 Share Posted November 10, 2005 Strange my cars fine with a 22% rack but maybe I'm used to it. It does kickback a bit on the road but isn't it a case of "they all do that" 😬 Rob G www.SpeedySeven.com Link to comment Share on other sites More sharing options...
EFA Posted November 10, 2005 Share Posted November 10, 2005 Myles, Simple calc. A std steel cased rack is 2.25 turns lock to lock. An 8% rack (which has been std on all models since about 1997) is 2.25 x 92% = 2.07 turns lock to lock. A 22% rack (which has been optional on all models since about 1994) is 2.25 x 78% = 1.75 turns lock to lock. We expected you to know this. Link to comment Share on other sites More sharing options...
Myles Posted November 10, 2005 Author Share Posted November 10, 2005 Uh, thanks Arnie... ...CC tech-help seem to think that an 8% is 1.8ish and a 22% is 1.65ish though - if they can't give a sensible answer.... If a 22% is 1.8ish, then my rack was changed between the car competing in the '01 Academy and it reaching me - not at all impossible, but undocumented. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Barry Posted November 10, 2005 Share Posted November 10, 2005 Arnie, Simple calc. A std steel cased rack is 2.25 turns lock to lock.is this a rack for cycle wings or for clams? Link to comment Share on other sites More sharing options...
EFA Posted November 10, 2005 Share Posted November 10, 2005 Clams live in the sea. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted November 10, 2005 Share Posted November 10, 2005 A rack that has been fitted to a narrow track cycle winged cart may have been limited in its travel. If you have racks of a similar vintage, the pinion can be simply swapped to get the change in ratio. This allowed me to get a widetrack 22% without having to swap track rods, before they started speccing the 22% racks with the longer track rod arms. 8% with full travel is over 2 turns. 22% with full travel is ~1.75 turns Link to comment Share on other sites More sharing options...
CB Posted November 10, 2005 Share Posted November 10, 2005 and to make things even less clear - the recent Roadsports have an 8% rack (at least that is what I was told) and CC list them as having "1.93 turns lock to lock" Link to comment Share on other sites More sharing options...
old captain slow Posted November 10, 2005 Share Posted November 10, 2005 22% is fine. You get used to it very quickly. C7 CDW Link to comment Share on other sites More sharing options...
Mike Bees Posted November 11, 2005 Share Posted November 11, 2005 Yup, any problems with kickback, 'bit of a handful' etc. are likely to be setup related rather than rack-ratio-related. Mike Link to comment Share on other sites More sharing options...
GTD Posted November 11, 2005 Share Posted November 11, 2005 Myles, given the race history, and the amount of documentation you have with the car, I'd be very surprised if you had anything other than the standard rack. Want me to try mine (if I make it home from work this weekend?) G for Geoff Link to comment Share on other sites More sharing options...
Myles Posted November 11, 2005 Author Share Posted November 11, 2005 Geoff - if you wouldn't mind... I'd be surprised if it had been changed. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
GTD Posted November 11, 2005 Share Posted November 11, 2005 Will do - we're looking for 1.8 turns lock to lock? Likely to be Sunday afternoon! G for Geoff Link to comment Share on other sites More sharing options...
Myles Posted November 11, 2005 Author Share Posted November 11, 2005 Yep - basically we seem to have three options for cycle-wings. 2.13ish, 1.8ish and 1.65ish. Basically, anything under 2 will be 'good'. Thanks. There's no rush - I've still not got a date from CC Midlands as to when they can pick the car up for the Arch work - so I'm not going to order a rack yet... Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
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