Early Bomber flex

I have a set of 2001 Z1 Drop Offs.

They have a bit of flex, the previous seller replaced the seals and oil before i bought them, but the bushes were not replaced, i managed to pick up a genuine set of bushes about a month back so i swapped them out, this improved things a lot! but they are still pretty flexy.

Hitting something like a root on an angle has the wheel deflecting away from the direction i want it to go in, you get used to it, but its not ideal.

Is this just a "feature" of old bombers? they are awesomely smooth and plush, they just twist and flex a bit too much for my liking.

FWIW these are the versions with "cryo" stanchions/steerertube/crown but 3 piece lowers that bolt together.

Wondering if the 3 piece lowers are causing the extra flex ?

I had some Z1 MCR's and they do flex a bit. They were better than the Psylos that they replaced, but not a patch on the Fox Vanillas that replaced the Z1's.

One of the issues is the stanchions are the same length for the 100mm forks as they are for the 130mm forks. So when in the longer travel mode there isn't a lot of stanchion inside the lower legs. Also by modern fork standards the stanchions are pretty skinny.

I certainly notied how much stiffer a set of later RS Revelations were compared to my 2001 Z1 MCR's.

Its just how things have gone, as forks have progressed they have gotten stiffer!

Maybe try a good brake booster first, basically adds an extra arch, clamp the wheel in firmly with a proper steel Shimano QR.

The QR20 versions are probably going to be a lot better but there doesn't seem to be many around.

Converting to 100mm will improve things, just need new main and top out springs.

I have a solid 9.5mm bolt on front axle on mine which helped a bit.

Never thought about a brake booster though, could be a cheap idea!

And they look pretty retro.

I don't think a brake booster will add any additional stiffness I'm afraid.

Check the bolts into the brace are tight. Sometimes if they have been completely dismantled the lower legs can be assembled "on the squiff" making for an overly flexi feel.

The 10mm bolt through option is a good idea hub allowing.

I added additional stiffness to mine (see my Kona link below) using a BETD brace. Much beefier than the original.

letmetalktomark":1a7tku8r said:

I don't think a brake booster will add any additional stiffness I'm afraid.

Check the bolts into the brace are tight. Sometimes if they have been completely dismantled the lower legs can be assembled "on the squiff" making for an overly flexi feel.

The 10mm bolt through option is a good idea hub allowing.

I added additional stiffness to mine (see my Kona link below) using a BETD brace. Much beefier than the original.

Click to expand...

If its the M-Arch models then you can't replace the brace.

And a brake booster does work. I've tried it and it does make a difference. Makes sense that it will, as it adds another point where the lowers are tied together, additional to the brace/arch on the forks themselves.

BITD bombers were known for being pretty flexy, I've had loads of pairs, and the only ones pre 2002 that didn't flex too badly were some 2000 Z1 duals, I remember the Cannondale stand at bike 99 had a set of bombers and a headshock to show the difference in how they flexed, they were rigged up to some sort of stand which simulated the pressures put on a fork while riding (I think) It was a real eye opener. That being said, it didn't stop me buying a set of Z2s the year later, they just looked great, and for the style of riding I do were never going to break.

Bombers

What front hub are you running? A lot of cup&cone hubs are a bit more prone to flex as the hex nuts on the end of your axle dont prevent deflection between the dropouts as much as something like a hope fatso or other suspension specific hub with a bigger contact patch.

Not sure on the brand of front hub, i had some spares in my box, i stripped them down, sprayed them a nice copper coloured paint, then converted them to solid bolt on axles with track nuts.

They seam pretty tight!

The 9.5mm front (i cut down a rear axle for this) is pretty tight in the dropout for sure, they are cup and cone.

They are the M Arch versions with the removable lowers, i have rechecked the lowers but they seam like they are fitted properly.