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19 Sherco head stock issue, advice required

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Hello, I’m new this this site so hope this is in the correct topic. I have a 19 factory Sherco st 250. Being a year old I thought I would change the head race bearings. After installation I have a strange issue with the yolks looking on the p***. Also when you eye the Stanton through the head tube it looks to not be parallel. See pics. Cheers 

7FDB0E42-17ED-427D-9FF1-86BFF8D24EE6.jpeg

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  • Author

Hello. No not knackered I just hadnt greased them all year so the steering was knotching slightly 

I would suggest that the fork mounting bore on the top and bottom yokes has not been machined square and true to the outside profile?... if the outside profile had been machined square to the bored but not to the centre spindle hole then you wouldn’t have been able to slide the fork stantion through both the bottom and top yoke. It does look a bit strange though ?

For next time: you should never need to mess with the head bearings/races, other than to grease them once a year. They'll last for eternity.

Edited by heffergm

It might be that sherco have machined the fork mounting bores mot parallel to the steering spindle to open up the steering angle a bit?

You're going to need to find another Sherco to find out if you're at all unsure of your work. I would think that if things were really screwed up though, you'd have never gotten the forks back into the triple clamp. If there was anything other than normal resistance when you put them back in, I'd be worried.

Did you actually replace the races and the lower press fit bearing?

Edited by heffergm

I’m assuming you didn’t need to prise open the stantion clamps on the yokes to slide the forks through both top and bottom yokes?... if you did then the head bearings aren’t set fully in the head stock 

Looks like they are intentionally machined like that to obtain a specific rake and offset. 

Did you unscrew the spindle from the bottom yolk? if so could the bottom yolk now be upside down, I'm just clutching at straws for you Steve.

From the pics, bottom triple clamp looks to be the correct way up (the voids facing up).

Edited by heffergm

  • Author
54 minutes ago, thall1 said:

It might be that sherco have machined the fork mounting bores mot parallel to the steering spindle to open up the steering angle a bit?

I did think this as the stantions slide up with ease. 

  • Author
1 hour ago, thall1 said:

I would suggest that the fork mounting bore on the top and bottom yokes has not been machined square and true to the outside profile?... if the outside profile had been machined square to the bored but not to the centre spindle hole then you wouldn’t have been able to slide the fork stantion through both the bottom and top yoke. It does look a bit strange though ?

Yeah the stantions slide up with ease it’s just strange like you say

  • Author
59 minutes ago, heffergm said:

For next time: you should never need to mess with the head bearings/races, other than to grease them once a year. They'll last for eternity.

Thank you. I will bare this in mind 

Here's an old pic of mine. Seems to show the same effect... maybe? Sorry, don't have it anymore.

 

Schermata_2020-01-16_alle_3_25.04_PM.png

Edited by heffergm

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