Harrison Billet 6 pot caliper

[Fil]

I've just ordered one for my Mastiff...

Not cheap I've had enough heart-in-mouth crap front brake moments so thought I'd spend the cash and see how much better it will be.

I'll keep you posted once it arrives in a couple of weeks

[Garf]

I have been waiting for somebody to spend the cash on one of these!!

I considered one but came by a bargain Beringer 4 pot ( ex Wonky) that I couldnt pass up.

The Harrison Billet 6's certainly look like the dogs danglies .... a quality bit of kit that bolts straight on with no adaptors. Very nice.

I will be interested to hear your comments once it is fitted.

Cheers
Garf

[kman.45]

I didn't see a direct listing on the Harrison website, so what model fits? Can anybody else share what other brake caliper fitments fit as a direct bolt on?

[Garf]

Check www.billet.co.uk and click the 'new products' tab on the left hand side of the page. The caliper is listed for the MUZ Mastiff. I guess it is on the fitments list somewhere but I couldnt see it when I checked today.

I havent heard of any other direct fitment alternatives but as long as you get a caliper that will clear the spokes when lined up with the disc you should be able to get a bracket fabricated without too many dificulties.

Mine is a Beringer 4 pot and the bracket is just a simple flat plate steel affair. I have also heard that a VFR caliper with appropriate bracket will fit and I dont doubt several others from Jap superbikes.

Another UK company, www.pretech.co.uk dont curently have a fitment listed but will make one if you can supply the dimensions.

Good luck

[Fil]

As Garf says, the biggest problem with getting a caliper to fit is getting one that will clear the spokes. Many are too wide to fit.

I bought a nice Brembo 4 pot off a Ducati Monster in the hope it would fit if I made a bracket for it. Sadly it's too wide. If the wheels were cast it would be much easier, but I prefer the look of 'proper' spoked wheels anyway.

[kman.45]

So are "most" 4 and 6 piston brakes going to be too wide? Sounds like that is basically the reason we have one dead side on both front and rear brakes? Are the Beringer and Harrison designed to be slimmer?

[Garf]

I havent seen the Harrison fitment on an MZ but I would hazard a guess that they wouldnt have altered their basic caliper design to cater for a relatively unpopular bike so I suspect that they are quite slim generally.

My Beringer is also slim compared to units I have seen on other bikes like my CBR etc.

I will measure it and post the info.

Cheers
Garf

[Kirk]

I would like to know how the new caliper works...

[Fil]

Have no fear, I'll be letting you all know how it performs, how it fits and all the rest once it arrives (should be within two weeks now - they're made to order).

They make 3 different basic front caliper types from what I can gather - a 4 pot, a 6 pot and a 'mini' 6 pot. The one for the Mastif is a 'Mini 6', so I imagine it's quite a small, slim caliper.

[Fil]

Here's an update for those that are interested...

The caliper arrive last Tuesday, but I didn't have a chance to fit it until the weekend.

Firstly, the quality looks fantastic. It's a big old beasty, but it fits directly to the fork without having to use a mounting bracket, and just required one shim between each mounting lug to get the caliper sitting centrally over the disc. The inside of the caliper clears the spokes, but only by a couple of mm! The caliper uses 6 individual pads - 1 for each piston.

There have been a couple of problems so far though!
Firstly, I ordered a black annodised caliper, but was sent a clear annodised one instead! I was a bit annoyed at first, but having offered it up to the bike I realised it looks pretty good with the silver fork legs and polished rims. The guy at Harrison was more than happy to swap it for a black one, but I decided to keep the silver one. They did agree to give me a discount on my next set of pads though, which I am happy with.
The other thing is that the banjo bolt hole uses a different thread to the OE Grimeca caliper. The 6 pot jobbie uses an M10 x 1.25 thread, while the Grimeca is also M10, but uses a finer 1.5 pitch thread. To this end I ordered a stainless bolt off the internet yesterday. Once this arrives I can finish the installation...

[handsomejackuk]

Fil,
a2stainless.co.uk do the banjo bolts in stainless and they are real cheap. where did you get your banjo bolts from ?


Al....

[Fil]

I got mine from moto-racing.co.uk - they're the HEL ones at £2 a piece.

I looked on a2stainless first, but they're out of stock. Just as well because the ones from moto-racing are were cheaper than a2.

[handsomejackuk]

Fil,

Wish i'd found that website will use them next time. I did have a look at ma nd p but they wanted £10 each for stainless banjo bolts. I got some nice stainless banjos on my other bike my TRX they have a scooped out head I think they may be goodirdge items they came with my goodridge hoses. I am too fussy with detail, i like the look of a bike that is engineered well if you know what i mean.... I like to see detailed stuff all the things you can see need to be right.........


Al.......

[Fil]

The bolts arrived today, so should be able to get the caliper fitted and bled later today.

I know exactly what you mean about detailing Al...
I've been trying to go over my bike and replace all the non strength- critical fasteners with stainless. I just need to get some flanged dome head bolts and penny washers and I'll have done a fair chunk of them. There's nothing worse than seeing a bike covered in furry brown nuts and bolts. I just wish the finish on the engine casings wasn't so crap!

[Fil]

Time for an update!

I finally managed to get time to bleed the brake and take the old girl for a quick spin at the weekend. So after the initial problems with getting the wrong colour caliper and the banjo bolt thread pitch being different, I can thankfully report that the brake is AWESOME

The feel at the level is nice, you can modulate it well and the lever feels much firmer than I could ever get it with the original 2 pot jobbie.
Two fingers is enough in most situations, and when you pull on the lever hard, the forks dive and the bike pulls up pretty quick. I could probably pitch myself over the bars if I grabbed too hard! With the old brake, the phrase 'lossing the front on the brakes' was not really something I ever worried about. More like locking the back and sailing straight on...
With the new caliper, you could easily lock the front if you wanted to.

So yes, I'm very pleased overall, inspite of the initial hick-ups. The brake is waaaaay more powerful than the original, but not too grabby.

The engineering is very nice, and the finish looks good, but only time can tell how it holds up.

It fits well with no need for ugly adaptor brackets - just a couple of shims (supplied) to go between the caliper mounting lugs and the fork lugs to centre the caliper over the disc. Doing this does make the back of the caliper sit VERY close to the spokes (no more than a mm - a Rizzla would struggle to fit between!) but nothing has rubbed it so far.

So is it worth the money? Well, you pays your money and you takes your choice. If you want a well made, very powerful front caliper that is designed to fit your bike, then yes it is.
There are alternatives like the many 4 pot calipers around for other Supermotos if you get someone to make an adaptor bracket, but they are designed to be used on machines that are lighter than our bikes. These would still be better than the original 2 pot caliper, but I doubt any of them will be as powerful as this 6 potter.

All I need now is to get a nice R6 disc with the ally carrier, and get some stiffer fork springs to stop them diving so hard when hit the front brake