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Discussion Starter · #1 ·
Hi,
I have just taken front end of my prophet apart to fit new headset bearings and whilst I had the lefty out I did the bearing reset procedure, but when I measure the fork as described in the manual it's only 690mm and not the 720-730mm the manual said it should be.
Anybody got any ideas whats wrong?
 

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Ridin' dirty!
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All lefty Max should be around 720-730mm long when you removed the internals and do the bearing migration (reset) procedure.
I had to reset the bearings on my brand new fork. :madman:
I just hold the uppers and carefully slap the lower axle part with a soft rubber mallet.
Do this carefully a couple of times and don't whack it too hard! :bluefrown:
Just tap it several times and re- measure.
That should extend it back to 730mm. :D
 

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Discussion Starter · #5 ·
I have given it a few good whacks but it's not moved at all!
When I remove the boot and cycle the fork 3 of the inner races seem to be wiped of grease but the 4th is untouched. Is this indication that 1 of the bearings is well out of position and what can I try next to fix it.
Cheers,
 

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Have you definitely taken the top cap off and removed the split ring so the fork can extend past it's normal full length?

If so, try hitting it harder!
 

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Discussion Starter · #8 ·
Well after 30 or so Thor like hammer blows latter it's now 728mm long.
I don't think the guy that owned the bike before me ever touched it in 18 months.
Thanks for the help.
 

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Hybrid Leftys aren't real
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Cool technique, but considering the potential damage that exists in using a multi-directional impact generator, consider leaving the wheel on, grabbing it, and thrusting downward forcefully.:thumbsup:
 

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Yep, you have to be very careful with hitting it. That's why I built my own little tool that presses the fork leg out. :) Only works with the internals removed though. :madman: You can only reset the bearings by pulling on the fork leg. If you just have to push downward they would reset after every jump when bottomed out and there would be no need for a "bearing migration reset", right? By overextending the fork the bearings actually roll up. I have used this "pull out" technique every since the first HeadShok came out in 92'
Cheers.
 

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how often

are you resetting your bearings? Just curious if too soft of a spring makes this more frequent or migration just happens when it happens.

REEK
 

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Discussion Starter · #13 ·
I tried the other techniques mentioned on versus threads without any success before taking the rubber mallet to it!
As yet I don't know if forks now working right as I'm still waiting for new headset and wheel bearings to arrive before I can get back out for a ride.
The " little tool that presses the fork leg out" sounds interesting. If I have problems again I might ask for some details.
 

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Hybrid Leftys aren't real
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Bloated Badger said:
I tried the other techniques mentioned on versus threads without any success before taking the rubber mallet to it!
As yet I don't know if forks now working right as I'm still waiting for new headset and wheel bearings to arrive before I can get back out for a ride.
The " little tool that presses the fork leg out" sounds interesting. If I have problems again I might ask for some details.

Mallet's a bad idea. Downward thrusting is the factory specific method.... with the top end removed as per the directions of course.:thumbsup:
 

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That's right. :yesnod:
First I thought you meant pushing down on the handlebars. :rolleyes:
With the top cap removed and the bike in the work stand thrusting down works of course.
Sometimes I just have to tap it with the rubber mallet to get the result I need. :thumbsup:
If you hit it too hard the bearing races might fracture or warp which then leads to even more trouble. :madman:
 

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Hybrid Leftys aren't real
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vitaccop said:
I would be afraid of damaging the axle strut by beating it with a mallet...
The boot, the frame, yeah, can't say I'd ever consider it, the conventional method works just fine. If it takes a hammer, chances are pretty good your bearing preload tolerance is way off.....:thumbsup:
 

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I just reset my MAX 140 last weekend when I did a spring change.. it took all of 10 seconds... I just forcefully extended the fork a few times while the front wheel was still attached and the bike was in a stand- no mallet necessary. It seems like people are making this much more complicated than it really is.. no tools or major disassembly necessary.
 

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Discussion Starter · #19 ·
Ok I take your comments onboard and thank you all for the concern you show for the welfare of my prophet, but all the telling off your giving me make me feel like a naughty school boy again!!
To put your minds at rest it's all working fine now.
Cheers
 

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I don't think there is any intention of insulting you or saying you are stupid.. the whole point of the forum is to share info and learn new stuff.. all everyone is saying is that using a mallet to do a bearing reset could lead to damage to the Lefty- that's all.

That being said.. I know how you feel about getting 'beat up' here.. I've posted a few reasonable questions in the past and the super smart-a$$ replies made me quit participating for a while.
 
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