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Morning all,
Prob just gonna try it anyway- but thought I'd ask some perspectives anyway.
I know this will void any warranty- and I don't have one anyway as I bought the frame 2nd hand.
So I've bought a Solaris Max 2 frame as an experiment with going back to a hardtail- it came up used on ebay and had a punt.
It's supposed to be 29 or 650b+
I'm gonna try running it with normal 650b wheels and tyres but a 150 or 160mm Lyrik- I've got a set and a few air shafts kicking about of different lengths.
I've got all the parts off my full sus frame I'm selling and thought I'd chuck them on this for a winter bike before buying a new trail bike next spring.
This will obviously drop the height of the bike with the smaller wheels, but then slacken it and pick the bb up with the slightly longer fork.
Any thoughts? I know this voids warranty and I don't care as I don't have a warranty.
Geometry guru's what's your take on this idea?
I can't run 650b+ tyres as my 27.5 Lyriks are non boost.
I'll probably buy a 29er fork and lace some 29 rims onto the existing hubs at some point (nice dt-swiss hubs so worth keeping-I build wheels so it's not a major outlay to do).
Yeah I'd have thought that'll be fine (I assume no liability though...), you may find the BB a little low but I don't know whether it's on the low side or not to start with?
The reason there's a limit on fork length is that the longer the fork, the more leverage on the headtube area when you land from altitude, so the stronger it has to be. Running too long a fork on a bike means that the headtube cluster isn't strong enough so it's more likely to crack or snap off.
Enjoy your new bike...
Yeh, cheers for that. It's kind of at the back of my mind and hence asking the question.
At 150mm though they will only be 10mm over the stated travel limit and a 29er 140mm pike would maybe be of similar length to a 650b Lyrik fork?
I'm guessing?
More likely to snap or crack... maybe my front teeth aren't safe!
At 150mm though they will only be 10mm over the stated travel limit and a 29er 140mm pike would maybe be of similar length to a 650b Lyrik fork?
Yes but if you run a 29er fork presumably you are running a 29 wheel front AND rear so the angles stay the same.
I suspect you will find the BB and cranks too low. Especially if only increasing the fork travel by 10mm.
I’ve done a similar thing with a cheap brand x hardtail. It’s a 27.5 frame but I’m using Stan’s flow 26” wheels. I’ve bumped the fork up from 120mm to 150mm. I actually love it, it’s slack and low. But slightly too low. Handles downhills great, but I often clip the cranks on rocks during techy ascending and I have to be careful picking lines. I bought 170mm cranks. Should have gone 165!
It'll be low but not impossibly low. What's the BB drop on this version of the Solaris?
Also, the leverage from a 27.5" wheel and 160mm fork will be about the same as a 29" wheel and 130mm fork - it's the contact patch to crown that matters, not the axle to crown. So you'll be fine in that respect.
To keep the angles the same as with a 29" fork you'll need 20mm more fork travel to add the extra A2C length.
STA won’t be ideal.
The reason there’s a limit on fork length is that the longer the fork, the more leverage on the headtube area when you land from altitude, so the stronger it has to be. Running too long a fork on a bike means that the headtube cluster isn’t strong enough so it’s more likely to crack or snap off.
Except that when you land a big hit, you'll be bottoming out.
Of course over several smaller hits you might initiate and propogate a crack. And it might be designed for less hooliganism than the longer fork will encourage. And it is going to increase the chance of a failure exactly where you really don't want a failure.
But if you're not at the heaviest/wildest riding end of the spectrum for that frame, you should be OK. Keep an eye on it though, you really should check the welds in particular and frame in general for cracks every ride anyway.
Double post
The reason there’s a limit on fork length is that the longer the fork, the more leverage on the headtube area when you land from altitude,
Really?
Doesn't the fork compress?
Yes but since the impact isn't in line with the fork, there's a component of the force orthogonal to the axis of compression of the fork, so it flexes.
Clearly any high impact on a fork is when it's compressed.