Semi-hydraulic disc

Hi.

Just got my self a grimeca semi-hydraulic disc brake setup for my 20mm PK frontend.

How much stopping power are theese supposed to have, beacuse mine don’t have much.

it’s much better than my sprint drum brakes, but i think i have seen PK drum’s that are better.

you need everything…
the worst thing to get is the upper mounting bracket for the damper. out of production and impossible to get. i hade to make one out of flat iron.

you need all shims, o-rings, circlips, steering bearings little parts for the speedo.

if you got coplete forks, you are sorted, then yu have everything you need, but if you got the bare sttering-colum like me, prepare to look around for alot of little shit.

The same shock won’t fit, so, time to get a preformace upgrade.

the steering stops shold fit, atlest they did on a 50 special i once had.

you should try it with the standard drum brakes first, those are not so bad.

Ah, brilliant, I was just about to compose a brand new thread about the very same things (and probably email avenger as well… sorry, but you are too knowledgable about smallies!)

Just (this very day) got a pair of PK 20mm forks, what do I need to get them into my Prim and get a semi or full hydraulic disc working on them?

I have seen other comments that say the SIP kit doesn’t include some stuff like speedo drives etc…

Cheers

Jim

Cheers

Will the same shock fit?

I’m not actually sure what I have and haven’t got… there is a steering column, and a mudguard, link and hub.

So I’m guessing that there will be the upper mounting bracket for the damper as per mr 210.

Avenger am I ok to send you a couple of photos of what I have so you can confirm?

Cheers

Jim

My setup gives great one finger braking. Yours may need bleeding or topping up for extra performance. Don’t leave your outer cable housing to long as i found this too hindered performance. If you pull your brake and see the outer flexing too much then trim a small piece off as a starting point and don’t froget to put top hat on the slave cylinder arm.

yeah assuming you do have the complete fork and your sticking it in the primmy you will need to redrill a hole for the steering lock as the pk forks (or at least the pk forks i have) do not have the correctly postioned hole cut for the brass steering lock collar to mate with. You will see what i mean when you compare the primmy and pk steering columns. I can’t remember whether I altered the steering bump stops on mine also. Your scoot will sit slightly (ever so ) higher at the front so you’ll need to find a suitably longer speedo inner/outer. I am using a 150 super speedo with 150 super inner an outer but that was down to personal preference.

Mudguard fixing holes also need tweaking to suit. If this all sounds a bit daunting, just neck a few stellas, get into the workshop and go for it with your new found confidence and lacklustre approach towards modifications. Mr 210 sounds like he’s had his work cut out for him !

the PX bracket is to big. you can properly slot the holes and maki it fit, but i made mini out of a app. 10mm thick flat iron. makes my shock sit a bit higher, but with the RS24 shock i’m just fine anyway.

the upper mounting bracket from a ET4 lokks like it might be the right one, but i’m not sure. was dismanling a crashed ET4 the other day to get the right shims for my frontend, but dint have the time to take of the braket. mate of mine says it’s the same as PX, so i’m trusting him.

if you have the hub complete with backplate and all, you got everything you need for the disc.

no, not the whole link. just the carrier and hub.

go for the 98, the calipers have bigger pistons and are way better.

Original von breezer: Well after stripping the mudguard off the forks etc I have discovered I do NOT have a mounting bracket for the shock. Would this be the same as one from a PX? and does anyone know if these (PX mounting brackets) are available?

Mr 210 what did you make yours from and has it worked okay?

Forks have already got a bitubo shock on, was hoping that would fit but no it definately won’t!

Looks like this is going to be another of those jobs that people say „slots in“ but is actually a right hassle…

What exactly do you get in the disc brake kit?

Do you get a whole link? (from fork through hub and caliper carrier, or just a caliper carrier to fit onto the existing link?

And which one has everyone plumped for the classic or the 98?

All information gratefully recieved?

Cheers

Jim

Well after stripping the mudguard off the forks etc I have discovered I do NOT have a mounting bracket for the shock. Would this be the same as one from a PX? and does anyone know if these (PX mounting brackets) are available?

Mr 210 what did you make yours from and has it worked okay?

Forks have already got a bitubo shock on, was hoping that would fit but no it definately won’t!

Looks like this is going to be another of those jobs that people say „slots in“ but is actually a right hassle…

What exactly do you get in the disc brake kit?

Do you get a whole link? (from fork through hub and caliper carrier, or just a caliper carrier to fit onto the existing link?

And which one has everyone plumped for the classic or the 98?

All information gratefully recieved?

Cheers

Jim