IP-057 Full Build - Need Advice

[Sitar_Ned]

Awesome build, Turbo.

I'm interested in the seat as well so plz do keep us updated. Sounds like it's already noticeably less comfortable, but who knows, you may adapt and end up actually liking it more.

You have a total weight yet?

Regarding you question about whether the star nut and top cap compress the stem and headset  or not.. They do. I wondered the same thing.

[Carbon_Dude]

Getting back to the headset discussion that Turboenterprise was posting about.  I took apart the stack on my IP-036 and yes the top bearing is above flush.

The reason I took apart my stack was that I felt movement in the headset even after several attempts to tighten everything down.  Turns out my upper bearing and cup have some gap between them.

Upper cup ID = 42.1 mm (spec is 42 ± 0.1), so this is still in spec.
Upper bearing = 41.8 mm (spec is 41.8 mm ± ?) bearing is nominal

So what I'm feeling is a 0.3 mm gap when I grab the front brake and tilt the bike onto the front wheel.  Very small amount of movement but I can feel it.

Once I knew there were no real issues, I packed the top headset with extra grease and reassembled.  Seems okay but it's interesting that my IP-057 does not have any movement in the upper headset.

Also, I noticed the lower headset is very snug.  Unlike the upper bearing, the lower bearing needs to be coaxed into the cup, compared to the upper bearing which just drops in.  So I looked up the tolerances of the lower portion of the headset and found this:

Bottom Cup Spec: 52 mm +0.05/-0.0
Bottom Bearing: 52 mm ±0.01 (very high tolerance)

So where the top can be +0.3 mm, the bottom can only be +0.06 mm, much tighter and in reality it feels very tight compared to the top bearing.

[turboenterprise]

Awesome build, Turbo.

I'm interested in the seat as well so plz do keep us updated. Sounds like it's already noticeably less comfortable, but who knows, you may adapt and end up actually liking it more.

You have a total weight yet?

Regarding you question about whether the star nut and top cap compress the stem and headset  or not.. They do. I wondered the same thing.

Update on the seat.  Also, everyone thinks I am crazy and have a taint of steel for riding it.  If your only interest in weight then go for it but comfort comes second. 

[Sitar_Ned]

Thanks for the update Turbo. Looks like I'll be avoiding that design.

[brmeyer135]

Is that crack all the way through?
I would put some tape of some kind on there to keep it from grabbing my clothes...depending on bad it is.

[turboenterprise]

No its all the way through.  I put a piece of clear gorilla tape over it.

[jonxmack]

That thing looks mean as hell!

Agree with the 32t front by the way, I only have a standard 11-36 10sp on the back but have never been undergeared, I am tempted to go to a 30 front to give me a bit more use of the cassette but since XX1 rings are $£$£ I'm kinda reluctant to until I find something I have trouble with!

[turboenterprise]

I have some bad luck.  I cracked a rim on a down hill section that I hit must of hit pretty hard.  I noticed it because the tire went flat. I love this bike but wishing I had two for when things like this happen. 

[MTB2223]

Damn, that's really bad luck! I hope it's possible to fix this rim.

I think I'll be happy that I've two sets of wheels.

[brmeyer135]

It is interesting that on page 5 you said that you ran the 2.4 to protect the rim - and bam you cracked the rim
Is that the front or rear rim?

[Vipassana]

That's a bummer.  Are those dark spots on the tire sidewall cuts in the sidewall or just marks?  I suppose anything can be broken if the conditions are right, but I was hoping to see the hookless rims be more robust.  Hopefully this is just bad luck.  I have 3 sets of these rim (myself and my teammates) and I don't want to worry.

What pressures were you running?

[turboenterprise]

I had just put air in right before the ride but it was somewhere around 22-28 psi.  I normally had been riding around 20psi tubeless though.  The dark spots are the wetness from the sealant coming out as I moved the tire to take the picture.  The tire does have a puncture in it though through the rubber where the rim cracked. 

Its the rear rim and I was running an Maxxis Icon because I had an extra one after i put a hole in the tread on the Maxxis Ignitor during a race a month ago.  I hadn't switched it back out to the new Ignitor I bought as I was still doing a lot of hard pack XC racing.  Most of my daily riding and training though is very rocky and technical riding so I guess I was asking for it. 

Ironically enough the guy I was riding with also blew out his rear tire on the same downhill section but he luckily didn't break a rim. 

V - I wouldn't worry.  I ordered an extra this time around (rear).  I figure I can use it for another build down the road but for now it will be an extra. 

[Carbon_Dude]

I guess you found, and went beyond the limit of abuse a carbon rim can take.  Running low tire pressure over downhill rocky terrain pretty much explains it for me.  It's interesting to see someone push the limits and see what they can get away with though.

I've put some hard miles on my carbon wheels but nothing like that I would say.  Georgia clay, gravel and roots are fairly kind to wheels compared to the terrain out West.

[turboenterprise]

Yeah I would say those downhill drops at speed (gps clocks at ~18mph) are deadly to a carbon rim.  Maybe with 30+psi it can consistently handle it. 

What pressure do most of you ride your carbon rims at tubeless?

[Vipassana]

I rode my race this weekend at 22 front, 26 rear.  Lots of very rocky sections with speeds up to 35mph according to my GPS.