Zephyr Front End Swapability

[Stereordinary]

I feel like I read somewhere that all Zephyr models have plug and play “swapable” front ends with each other, but I can’t seem to find where I allegedly read that, and I’m curious if it is in fact true. Obviously it’s doubtful anyone with a 750 would want a 550 front end, or an 1100 owner would install triples and forks from a 750. But for those of us that have a 550, the potential to “upgrade” to a 750 or 1100 front ends sounds tempting. Mostly because of aftermarket cartridge kit availability, but also potentially all new forks from say, Öhlins for example.

All I could find was that the forks from the 1100 are longer than others at 810mm. But with a 43mm diameter, that means the triples could fit the forks Öhlins makes for the ZRX, which would be an obvious improvement over any stock Zephyr forks.

So what do you all know about it? Are there any other things to consider? Has anyone here ever swapped a Zephyr front end?

[Freddy]

Might seem a couple strange related questions, but bear with me
1. what shocks and springs are you running on the back?
2. What tires (tyres) are you running?

[David Richard]

hi i have never tried it but a emulator can improve the handling if you can find one to fit the forks

[Stereordinary]

1. what shocks and springs are you running on the back?
2. What tires (tyres) are you running?

I had been running stock shocks and fork springs until just yesterday, when I installed new Öhlins KA143 shocks. And I’ve got some RaceTech springs to install in the front.
Bridgestone BT45 tires.

[Freddy]

1. what shocks and springs are you running on the back?
2. What tires (tyres) are you running?

I had been running stock shocks and fork springs until just yesterday, when I installed new Öhlins KA143 shocks. And I’ve got some RaceTech springs to install in the front.
Bridgestone BT45 tires.

Perhaps obviously my question was aimed at no point doing the front if the vastly more important rear and tyres aren't sorted first. Can I suggest before going to all the expense and hassle of fitting aftermarket cartridges (I think you'll find the units that fit straight into damper rod forks are generally the manufacturers budget units) you first try the relatively inexpensive cartridge emulators and a fork brace. That combination will work extremely well if set up correctly. And that is the key word, set up correctly. They are not just a drop in and forget solution. Getting the fork oil weight correct is a bit of trial and error. The mechanical setup is pretty straightword.

Be careful with your choice of spring weights. If I punch my weight and 750 into Racetechs spring calculator, it comes back that I should be running a pair of 1.0 rate springs. At first I thought I'll go to the lighter side and ran 0.95. They didn't last long (harsh ride, and endless pounded out steering head bearings) and it was down to 0.90's. Now I run 0.85's and the result is much better. This would be considered way underweight by the 'experts', but with properly set up rebound and compression damping works well. Ride is still controlled by comfortable. Does not just collapse under hard braking or trail braking into downhill corners. The most important improvement was dramatically increased ground clearance, which was a major problem early in sorting the suspension. Too heavy a springs in the front, and too light on the back mean the rear took all the downward forces when cornering hard.

P.S. even with cartridge inserts you'll need a fork brace. Those 'conventional' forks allow a lot of twist in the front,creating a vague feel when cornering, tyre wanting to follow road imperfections, etc.