I have a trike with an early k100 (i think) front end, front brakes are the early single pot callipers n they need a damn good seeing to...
Question i have is will the later twin pot callipers fit directly as a replacement as the extra umph in braking would be better for the trike...

Any help is appreciated thanks...

Nope. The twin pots are for the floating disks. Fix what you have and you will find that they work well or buy the whole front end including forks wheel and brakes from a later 16 valve bike and you will get better brakes.

As Bob says. There's a difference in offset by about 3mm (I think).

I never had a complaint with those front brakes once they were in good order. Did a fluid change after only 6 months and amazed the effect even that has..so now they get new fluid regularly. I have a K1100LT to compare it with and not sure the hassle and cost of a complete front end change would be worth it although plenty have done it.

Thanks for the replies, i was afraid of that tbh, the trike is a vw so has a fair amount of extra weight to stop...
I'm looking for a seal kit for the front callipers without goin to BMW themselves coz like HOW MUCH!!!

So if anyone can suggest a place in the UK that would be helpful...

Only other option I have atm, coz this thing is a money pit, is I have extended forks from a 97 daytona on my chop, might just scrap it n use it as a donor...

I wonder if a later 4 pot style master cylinder  at 16 mm  would be a better choice  to give more braking power to the front disks  than the standard 13 mm master cylinder
obvious to me is that a wide tyre would be needed also..

Nothing wrong with the standard brakes when they are working properly. You could throw money at it and change things, but you might as well just buy a different bike.

Ok I'm not sure people are even reading the pist now before answering...
I can't change the master cylinder as the front brakes now operate with the back from a foot pedal...
I am throwing miney at it but can't get a different bike as the thing is actually a trike...

The left callipers is leaking so i need to at least need to find a place in the UK that sell the seal kit...

Not meaning to cause offence with this next bit but please read all the post before putting in uninformed irrelevant replies...

sarcastic pig wrote:Ok I'm not sure people are even reading the pist now before answering...
I can't change the master cylinder as the front brakes now operate with the back from a foot pedal...
I am throwing miney at it but can't get a different bike as the thing is actually a trike...

The left callipers is leaking so i need to at least need to find a place in the UK that sell the seal kit...

Not meaning to cause offence with this next bit but please read all the post before putting in uninformed irrelevant replies...

Well I read the post and you mentioned the front brakes. The standard set up is the 13mm front master cylinder for the front brakes. Obviously something has been changed as the footbrake does not normally operate the front brake on any of the Ks. That would be 'linked' brakes and Ks don't have that set up. I don't see that mentioned in your post but then my mental telepathic skills tend to be clouded early in the morning. Some might say all the time.

As regards the brake caliper [and master cylinder] parts I think most of us do actually use the BMW parts BUT the single pot calipers are Brembo and the exact same calipers are also found on the BMW R bikes and Moto Guzzi as well. I have done the brakes on both the K100LT [ABS] and the K100RT [non ABS] and all the parts were BMW. Calipers got new seals, pistons, master cylinders got repair kits and new pistons all with huge improvement.

You did ask about getting an improvement on the original set up, changing calipers is an expensive option due to needing to change the front end which is why you were offered the alternative of a change in master cylinder.
Some have changed the master cylinder unit to do this.

You will be able to get the parts you need at Motobins https://www.motobins.co.uk/bmw-parts.php?model=K%20Series&bikeref=K100
I would advise you to also use stainless braided hoses as that will make a big improvement. If you need a rear M/C check out eBay and find a comparable, I found a Yamaha one new for $15AUD.

sarcastic pig wrote:Ok I'm not sure people are even reading the pist now before answering...
I can't change the master cylinder as the front brakes now operate with the back from a foot pedal...
I am throwing miney at it but can't get a different bike as the thing is actually a trike...

The left callipers is leaking so i need to at least need to find a place in the UK that sell the seal kit...

Not meaning to cause offence with this next bit but please read all the post before putting in uninformed irrelevant replies...

People are reading, but the post does not say that you are using a foot pedal instead of a brake lever as standard. 
As said the brakes work fine in standard form, but who would guess that you are using this foot pedal and who can guess what sized piston it has in it.
BMW will sell you a seal kit if you want to throw money at it. I might even have a new spare seal kit in my garage, but I can't be bothered to go and look.

Do NOT ask me why ('coz I've no idea  ), but a new P8 seal kit for the front brake is cheaper from Gutsibits than Motorworks. Usually anything that says 'Moto Guzzi' gains a instant increase in price even greater than anything that says 'BMW'.