Scooterotica

Hi all,

Just got my hands on a Protech rear shock and am wondering how to adjust the length of the unit? I understand the damper adjustment via knurled nob and understand the preload adjustment via C-spanner lock ring at the bottom of the spring, however, I understand that these also have up to 10mm length adjustment. How do you adjust length of the unit?

I appreciate that some others adjust in length by screwing / unscrewing the 2 eyes (top and bottom) in relation to one another. Is this the same for the Protech units?

Cheers in advance.

Adam

hi adam just got mine fit at chiselspeed last week fit to the scoot and while you sit on scoot full weight so someone holding headstock while you sit there and someone measuring the center between both nuts and under commpression it should be between 293 to 295 turn the big nut to get this then set damping to 7 or 8 clicks the main thing is to set the weight on the spring and not the damping

Hi Garry,

Thanks for the reply.

Yeah, I get the preload on the spring issue, by adjusting the big notched adjuster with the C-spanner, but that shouldn't alter the length between centres... should it?

OK, these are probably not too difficult for some to understand (obviously not me!) but I was still surprised that it didn't come with some instructions.

My reason for wanting to know how to adjust the overall centre to centre length is that it is going on a motor that has 'special' requirements so knowing how to adjust the length, should I need to, is important.

Thanks again.

Adam

Adam I dont think the Protec has adjustable length, it comes as two different models, 300mm for the series 3 and 310 for the series 1/2. They do talk about adjustable ride height but I assume that means spring preload.
Having said that I still think it's a nice unit.

I think you set it with 1/2 inch compression to take your weight and then set damper to suit your riding

Minority wrote:Adam I dont think the Protec has adjustable length, it comes as two different models, 300mm for the series 3 and 310 for the series 1/2. They do talk about adjustable ride height but I assume that means spring preload.
Having said that I still think it's a nice unit.

I agree there are 2 different lengths I think the only adjust is the spring and the damping

Morning guys,

Yep, I understand that Protech sell the shock in the 2 different lengths, which should be fine for most applications, but mine is slightly different and the 10mm (or so) length adjustment may (only may) be beneficial to use. This slight length adjustment was mentioned when I ordered the unit direct from Protech but the lack of instructions leaves me guessing.

I'll get back in contact with Protech directly and let you all know what additional info I might end up with.

Thanks again.

Adam

UPDATE - I've spoken with Protech and they tell me that the length adjustment that some people refer to in respect of their shocks is simply a case of not using all of the thread during assembly, thereby allowing some length adjustment. However, Protech would not recommend using this method of adjustment and would rather use all of the threaded element, with this being taken into account during manufacture.

As such, the Protech units are fixed length (from the horses mouth).

Cheers all.

Adam

hi adam,
ive looked at these shocks and they look quite good, i guess your wanting a bit of a lift at the rear to clear your manifold, not sure if you saw that they do extended tops as an option for some of there shocks, so im guessing that the damper rod must screw into the top mounting piece, maybe you could just add a shim/ washer between the two to increase the over all length, i see they do a custom service as well, maybe they could do it for you, or make an extended top to the length you require ?

holty

Hi Holty,

Better than that, they asked me what length of shock I wanted and they simply built me one to that length. With no length adjustment, I hope that I got it right! I do not have front of motor/frame clearance issues with a 315mm rear shock so hope that my 325mm is not too long (fingers crossed).

Protech also suggested upping the spring poundage to reduce the chance of bottoming out, suggesting a 400lb spring, rather than the 280-350lb progressive spring that they fit to their normal Lambretta shocks. The R1 or R6 standard spring of 480lb is normally considered too hard so time will tell how suitable the 400lb is. Protech did state that they build shocks for racers with far higher spring rating than 400lb and said that they thought 400lb would be fine for road use.

What I must add though is that Protech have been excellent to deal with and any error that might come to light would be the result of MY specification, rather than theirs. It was also very nice to give them my spec and have them build me a bespoke shock at no additional cost (great service).

Adam