Rear Shock

[Lord Stig]

Appologies if this has been covered before, but I've been unable to find info through searching the forum. I still think I've seen discussion on this since somewhere, but hey...

I've been trying to work out which of the AT shocks are interchangable with other AT variants. Honda list at least four part numbers for the RD04 on, but Ohlins list only one part for 1995 models on (HO645), suggesting that any RD07 shock will fit another. Likewise Hagon list one (M6107 for RD07s from 1992 (Ohlins' list only covers 1995 on). Technoflex has two options (55308-815-670 and 55208-815-670), which they list for RD07s from 1993 on. This leads me to suspect that one of the £175 OEM shocks advertised by Wemoto for the 1995 model would fit my 2001 RD07a. Anyone know any different? If the shock fits is the main problem, because from what I've heard here the damping was actually better on earlier models.

Any thoughts out there? Has anyone any experiences on aftermarket rear shocks (and forks/fork springs)?

Stig

[mal]

I bought a replacement shock (genuine) from Wemoto ,part number was different to what was on bike ,i had no problems fitting it to 94 XRV750-R ,i think i still have the box in the garage, i will post part number tomorrow if i can find it, part number is 52400-MY1-971

[mgillespie]

Sorta releated, Anyone know the size of C Spanner required to adjust the rear shock?

[Lord Stig]

The Hagon one fits, but because of the access I just tend to use a long screw driver and a hammer. Works fine!

Stig

[iswoolley]

...I've been trying to work out which of the AT shocks are interchangable with other AT variants. Honda list at least four part numbers for the RD04 on...

Stigy, it's very likely that externally the shocks for the various model Africa Twins were identical, and it's the internal parts that are different. It's possible that Honda had different shocks for different markets, or fiddled with the damper valves to try and improve the bike's handling. Hence 3rd party shock manufacturers can market just the one replacement, with adjustability to make it replicate the behaviour of the 4 different OEM shocks.

Not gospel, just my engineering opinion.

Iain

[Lord Stig]

Iain, that makes a lot of sense. I bet that's the reason! But from what I heard Honda actually managed to make later ATs worse rather than better! Ah well. On the plus side it means getting one of the Wemoto Showas, an aftermarket or even a 'less used' item from eBay should be Ok. If I get one and it doesn't fit I'll be sure to let everyone know the details...

Stig

[Lord Stig]

An update. I got hold of a used shock from Cambridge Motorcycles and Breakers last week (via eBay) for £19 inclusive of post and packing. It turned out to have a compression adjuster, and I'm pretty sure it's from an RD04. For the price I'm pleased because it will give me the chance to have a look at the differences and find out once and for all whether it's possible to fit the better RD04 unit to the RD07. I've been 'up North' for the last few days and only got chance to visually compare them with the original still on the bike last night. So far it seems that the lower and upper mounts are the same, but that there are two main differences. Firstly and most importantly, the unit appears to be around 20 mm shorter - odd considering the higher RD04 seat height. I notice the RD04 spring is 7 mm shorter than the RD07 according to the Haynes manual, but that doesn't account for the difference. maybe I'll find that the difference isn't as great as it seems from visual comparison, but 20 mm would surely alter the geometry of the chassis. If it doesn't I might have found a way of reducing the seat height for short arses! The second, less serious, difference is that the remote reservoir exits either out of the front or rear of the unit, meaning that the reservoir itself will need to be mounted further forward in its cage to avoid fouling the battery box (obviously not present on the RD04). Not a problem, as the adjuster will be more accessible.

I'll keep you posted....

Stig

[piguglyshandydrinker]

20mm shorter shock will have a massive difference on ride height I fear (2" - 3"?)

Could be a totally different linkage ratio too by the sounds of it.

Suck it and see, as they say

Phil

[Lord Stig]

Yep, I'm sure that's where the difference is because the part number is different between the RD04 and RD07. Even if it fits I would imagine the leverage could be adversely affected. Whether an earlier linkage would solve the problem is something I'd have to test by picking one up. I probably need to replace the bearings anyway...

Stig