Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Jul 23, 2021 at 10:18 Quote
Bear in mind, that the smaller 26" wheel doesn't need as large a cassette, to get the same low gear ratio as a bigger wheeled bike. A 50t on a 29er feels roughly the same as a 44t on a 26er. You are probably still going to want something a little larger than 34t, but if you drop a couple of teeth from your front chainring, you may not need to go much larger at the rear. You'll lose a little top speed, but you don't really need to pedal on the downhill bits anyway.

Posted: Jul 23, 2021 at 10:33 Quote
gabriel-mission9 wrote:
Bear in mind, that the smaller 26" wheel doesn't need as large a cassette, to get the same low gear ratio as a bigger wheeled bike. A 50t on a 29er feels roughly the same as a 44t on a 26er. You are probably still going to want something a little larger than 34t, but if you drop a couple of teeth from your front chainring, you may not need to go much larger at the rear. You'll lose a little top speed, but you don't really need to pedal on the downhill bits anyway.

Good call. It may be simpler to just put a smaller ring up front - maybe a 30T or even 28T. You may run into issues with crank style/ring mount options.

Posted: Jul 23, 2021 at 10:33 Quote
Does anyone know what fork oil and how much I need for f-series 80 mm forks? Having a bit of trouble finding what I need.

Posted: Jul 23, 2021 at 10:56 Quote
T00Holmes wrote:
Does anyone know if I can use offset bushings on my shock in order to steepen my HTA and raise my BB so when I mullet my bike is has roughly the same geometry as stock?

I emailed the guys at offsetbushings the exact same question few years ago. Their response was: "I really can't recommend it, they'll want to rotate when you ride the bike unfortunately."

Posted: Jul 23, 2021 at 11:30 Quote
Angryham wrote:
Hey guys long time no post!

Just a quick question - I currently am in the process of trying to modernise my 2012 Lapierre Spicy for a week in the Scottish Highlands in August. I currently run a 10spd 34T cassette on a 1x10 shimano drivetrain, with a zee derailleur.

I would love to upgrade my cassette to something with a bigger range; these dinner-plate sized cassettes i'm seeing on newer bikes look great and I feel that my current set-up means I have to really grind out the climbs (heavy bike as well lol)

Is it possible to upgrade to a much larger (42T?) cassette on this old 26" bike? I've heard that the Zees aren't compatible with larger cassette sizes, or even that 26" wheels aren't compatible with larger cassettes - can it be done, will I need to get a whole new rear mech etc? Thanks in advance

A range extender cog will work but not with a Zee deraileur, which doesn't have enough pickup. Zee is an SS and you need a GS or SGS.

Easiest way to do this is with the 10-speed 11-42T cassette and an 11- or-12-speed derailleur. I have that setup with a 12-speed Deore derailleur and a 30T ring on one of my 26" bikes and it works great with the 10-speed shifter.

That said, the other folks are right that all you need is a smaller chainring for the climbing but 30T is the smallest you can go on 2102-era 104 BCD cranks.

Posted: Jul 23, 2021 at 16:11 Quote
oatkinso wrote:
gnarcissistictendency wrote:
Bro there will be people saying that what I’m saying is bs lol but what I did with my Code RSC’s to shorten the lever throw was bought some Magura Storm HC rotors. They are 2mm thick and those along with a solid bleed and dialing in your contact adj will give you what you’re looking for

Cheers. When you say dialing in the contact adjust, do you mean something other than setting it at minimum?

Sorry for the late reply but what I mean by that is you should use the contact adjustment wheel to fine tune how quickly your levers engage the pads to the rotor. Hope that makes sense to you

Posted: Jul 26, 2021 at 10:35 Quote
Does anyone know if I can run a Sora front brifter on a 3x Deore dynasis front mech? If not what's a suitable replacement for a 2x mech on a 3x crank that runs 2x9 brifters? Making a total frankenbike right now. The rear 9-speed Deore works very well but I can't seem to get the front to work quite right.

Posted: Jul 26, 2021 at 12:01 Quote
gabriel-mission9 wrote:
jimbomodder wrote:
gabriel-mission9 wrote:

Yeah both of those springs should clip into the bottom of the plastic collar above them. One spring inside the other
right o, was strange thou as the clip and washer just fell out. No clue how the clip came off.

If I remember correctly (it's been a while) there should be 2 clips on the air side, one right at the end of the stanchion (which I *think* is the silver ring with the larger hole in your picture), and another one a few mm further in which is just a normal circlip. The fatter silver spacer goes in between them, and it matters which way up it goes. Get it the wrong way and the bottom clip falls out. Unfortunately I can't remember off the top of my head which way up that is... Sorrylol
rebuilt them today and when pumped up they show 120mm travel? Also one compression cycle and the springs all popped off again. Any ideas?

Posted: Jul 26, 2021 at 13:25 Quote
jimbomodder wrote:
gabriel-mission9 wrote:
jimbomodder wrote:
right o, was strange thou as the clip and washer just fell out. No clue how the clip came off.

If I remember correctly (it's been a while) there should be 2 clips on the air side, one right at the end of the stanchion (which I *think* is the silver ring with the larger hole in your picture), and another one a few mm further in which is just a normal circlip. The fatter silver spacer goes in between them, and it matters which way up it goes. Get it the wrong way and the bottom clip falls out. Unfortunately I can't remember off the top of my head which way up that is... Sorrylol
rebuilt them today and when pumped up they show 120mm travel? Also one compression cycle and the springs all popped off again. Any ideas?

how much travel are they supposed to have and how much pressure did you put in?

Posted: Jul 26, 2021 at 14:08 Quote
gabriel-mission9 wrote:
jimbomodder wrote:
gabriel-mission9 wrote:


If I remember correctly (it's been a while) there should be 2 clips on the air side, one right at the end of the stanchion (which I *think* is the silver ring with the larger hole in your picture), and another one a few mm further in which is just a normal circlip. The fatter silver spacer goes in between them, and it matters which way up it goes. Get it the wrong way and the bottom clip falls out. Unfortunately I can't remember off the top of my head which way up that is... Sorrylol
rebuilt them today and when pumped up they show 120mm travel? Also one compression cycle and the springs all popped off again. Any ideas?

how much travel are they supposed to have and how much pressure did you put in?
sold to me as 80mm. I put 75psi in.

Posted: Jul 26, 2021 at 14:32 Quote
I have a RockShox Pike fork (its a little older) and it is supposed to be a 160mm fork. It is sucked down in its travel so it only have about 140mm of travel. How do I fix this? I have 75 psi in it. Thanks!

Posted: Jul 26, 2021 at 15:13 Quote
noakeabean wrote:
I have a RockShox Pike fork (its a little older) and it is supposed to be a 160mm fork. It is sucked down in its travel so it only have about 140mm of travel. How do I fix this? I have 75 psi in it. Thanks!

The suck down is either because you have a vacuum in your lowers or because you have some gunk keeping your pos and neg air chambers from equalizing. In order of difficulty

1) burp your lowers by sliding a zip tie past the main wiper seal
2) burp the lowers by undoing the foot nuts and separating the lowers from the upper rods
3) remove your air spring and remove the offending grease plug, reassemble with an appropriate amount of grease

Posted: Jul 26, 2021 at 15:16 Quote
I have organic brakes pads on my SRAM Guide R and I want to switch for melatic one for more braking power. I check my rotor and it's compatible but I read somewhere: If you change the pad materiel you have to change de rotor cause they are already bend-ins.

So do I really need to change my rotor?

Posted: Jul 26, 2021 at 15:19 Quote
Jridyee wrote:
I have organic brakes pads on my SRAM Guide R and I want to switch for melatic one for more braking power. I check my rotor and it's compatible but I read somewhere: If you change the pad materiel you have to change de rotor cause they are already bend-ins.

So do I really need to change my rotor?

No, you just need to scuff the rotor surface with some sand paper to remove the bedded in organic material before you install your metallic pads.

Posted: Jul 26, 2021 at 15:25 Quote
Looking at buying a set of 2005-2007 Marzocchi All Mountain 2 forks for cheap. Reason they're cheap is that they apparently lose air while under weight, which would rule out a faulty schrader valve. Anyone have any idea what could be the issue? Based on my reading I understand that it can be as simple as a bad o-ring or possibly a bad air cartridge.

Thanks, any ideas would help!


 
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