Caliper forward or behind forks?

Yea, I meant the factory setup on single discs up to 1978 was in front of the forks, factory setup for dual discs was behind the forks. The 1977 KZ1000 was factory 1 disc in front of the leg. You could buy aftermarket dual disc conversion, and since your existing caliper was already set in front on one leg it was much easier just to add the second as a similar caliper in front of the leg on the other leg. Plus with switching to behind the leg you need a longer speedo cable, probably different length brake lines ect, so the thought was probably to minimize the work involved to upgrade to dual discs.

Summary of KZ900/1000 brake designs in 1976, 1977 and 1979 ----


1976 KZ900 brakes (last 900 and last rear drum)

Front brake caliper redesigned as one piece unit

UK model: dual front disc on front of forks

US model: single 6mm front disc on front of fork*
* Kaw offered factory kit for conversion to dual front disc on front of fork -- twin 4.5mm disc (reduce unsprung weight); junction box with extra outlet; another lower hose; right side brake pipe; right side chrome bracket lower hose holder; larger 5/8" front master cylinder

1976 LTD -- rear disc; dual front disc rear of forks


1977 KZ1000-A1 brakes:
Went from rear drum to rear disc
US model has single front disc on front of fork
Am guessing UK model kept dual front discs on front of forks. Also guessing Kaw still offered dual disc conversion kit for US models on front of forks.


1978 KZ1000-A2 moved single front disc caliper to rear of fork. Am unaware of any differences between UK and US models or any dual disc option offerings from Kaw.
1978 KZ1000-D1 (Z1R) had dual front discs with calipers on rear of forks.


1979 KZ1000-A3 and KZ1000-D2 (Z1R) had dual front discs with calipers on rear of forks.


Above is my understanding. Would welcome any and all corrections.

Thanks all. I really appreciate the help. I'll keep them forward of the forks. Just need to finish rebuilding them.

Just want to point out that if your bike was designed to have the calipers mounting in front and you "flip them around", your speedometer drive will now be on the right. If located on the right, it will turn backwards from its intended direction of travel and thus your speedometer will run backwards. This may not be desired. If there is a way to keep the speedometer on the left, then the only problem you will find is that the brake hose is not the correct length.

Huh??

swap the fork tubes and calipers left to right and the wheel stays the same orientation with the speedo drive on the original side. You are just swapping the forks to mount the calipers behind the tubes. The wheel stays the same.

The Fish wrote:

Huh??

swap the fork tubes and calipers left to right and the wheel stays the same orientation with the speedo drive on the original side. You are just swapping the forks to mount the calipers behind the tubes. The wheel stays the same.

I was thinking that exact same thing when I first read WG's post, but it makes sense to me.

I think what WG is trying to state is that if you leave the wheel mounted to the fork tubes and just slide them out of the triple clamps as an assembly to rotate them, then this will be a problem:

On my '78 KZ650, my '84 ZN700, and my wifes '96 VN750 there are two "tabs" protruding from the inside of the lower left fork tube. These keep the speedo drive unit in a specific postion, and prevent it from rotating and possibly causing the front wheel to bind (= a possible crash :pinch:) should the speedo cable become detached.
I imagine the 1000 has a similar or same setup on it's left fork tube, as all the KZ's were fairly similar in some regards.

900cows wrote:

Mounting brake calipers behind frt. forks was done to minimise tensile stress and movement of the caliper under braking,the main forces involed push the caliper against the fork legs (telelever/paralever setup)....

What did he say???:dry:

JimatMilkyWay wrote:

900cows wrote:

Mounting brake calipers behind frt. forks was done to minimise tensile stress and movement of the caliper under braking,the main forces involed push the caliper against the fork legs (telelever/paralever setup)....

What did he say???:dry:

With caliper(s) mounted behind the fork leg, under braking the caliper presses forward against the fork leg, which acts as an anchor of sorts, and is basically a stronger mounting placement.
With caliper(s) mounted in the front, under braking the caliper is actually pressing forward away from the fork leg, and the only thing providing support and strength is the 2 caliper mounting bolts.

A roughly 3" diameter fork tube plus the 2 caliper mounting bolts together IMHO is much stronger/less prone to flexing than just having the 2 bolts alone to rely on.

Post edited by: RetroRiceRocketRider, at: 2007/02/11 12:47

I dont know. I think that the 2 bolts that hold the calipers on are what anchor it to the fork leg reguardless of if it has a push or pull to it when the brakes are applied and I think either would be as strong as the other.

From what I understand, the calipers are put behind the fork tubes to put the weight of the calipers lower on the fork leg to help with cornering.

When you are leaning in a turn the weight of the high mounted foward calipers tends to fall towards the inside of the turn (the weight of it is higher/taller and has more "leverage" when pulled down by gravity).
When the calipers are mounted behind the forks, the weight of the calipers is conciderably lower on the fork legs and affects the cornering less than the high foward stock placement of the calipers.

Fish and R4 are right. Calipers behind the forks are the better design in every way, that's why all later (and modern) bikes have em there. So it really does depend, like someone put it, on how much of a purist you are. Swapping the forks (don't flip the wheel) is easy as pie just get some stainless lines.

Post edited by: dutchz, at: 2007/02/11 19:49