MTB fork upgrade - help!

Lumen

So I bought a Trek Marlin 5 for my son.

The forks are predictably awful so need upgrading.

What I want is a decent air fork that's just a slot-in replacement without altering the geometry, axle type or brake mounting.

The brakes are post mount and the axle is 9mm QR.

This isn't absolutely straightforward as the 13.5" frame model has an 80mm travel 27.5" fork. I presume it has an 80mm fork to reduce the axle to crown distance.

The forks have Suntour SR XCE on them, and a 27.5" sticker. I scanned the QR code on the fork and it gave me:

SF18-XCE-DS 27.5 TS
170/0
:F/C:YS727 CP GA19-06A(S)T80
;SFB-I52740-D01;CP201805302366296

This "XCE" fork doesn't seem to exist on the internet.

The cheapest 13.5" Trek with an air fork is the X-Caliber 8.0

https://www.trekbikes.com/ie/en_IE/bikes/mountain-bikes/cross-country-mountain-bikes/x-caliber/x-caliber-8/p/23156/

RockShox 30 Silver, Solo Air, rebound adjust, TurnKey hydraulic lockout, tapered steerer, G2 Geometry w/51 mm offset on 29ers, 100 mm travel (13.5: 80 mm travel)

A Gold would be even better.

Can I find this fork anywhere in 80mm/27.5"? Nope.

So any ideas? Other than speak to the shop, obvs.

Buzwaldo

Posted in the wrong forum. Try hereðŸ˜

https://touch.boards.ie/forum/1841

Lumen

Buzwaldo wrote: »

Posted in the wrong forum. Try hereðŸ˜

https://touch.boards.ie/forum/1841

No way, it finally happened!

Lemming

Lumen wrote: »

A Gold would be even better.

Can I find this fork anywhere in 80mm/27.5"? Nope.

So any ideas? Other than speak to the shop, obvs.

AFAIK, most of the Rock shox forks allow for adjustment; in this case between 80 - 120mm. It will require some technical know-how but from what I understand it's reasonably trivial to do, or just speak to a shop about it.

rizzodun

The Marlin should take a 100mm fork without affecting the geometry too much, this would give you more options for the suitable fork. Regarding QR, you can always pick up a new front hub/wheel if you need to change the QR type.

steamsey

Lemming wrote: »

AFAIK, most of the Rock shox forks allow for adjustment; in this case between 80 - 120mm. It will require some technical know-how but from what I understand it's reasonably trivial to do, or just speak to a shop about it.

I think in general forks can be modified. Had a set of 80mm Fox Floats years ago that I had pushed out to 120mm by OC Tuning at the time. Cost €150. Made a big difference to handling on the XC bike they were on. Spoke to few people at the time who said 40mm adjustment to stock forks is limit they would try, so you should be ok with 20mm difference from stock.

I doubt the average mechanic could do it themselves, but as said, 80 / 100mm won't massively affect geometry - and if it does, you can probably get the 100mm changed to 80mm. Chain Reaction have the RockShox Gold 30 in 27.5 / 100mm with 9mm QR.