Sanity check my P9 build, please!

[deezums]

Hello everyone!

I'm pretty new to MTB, went riding with some friends a while ago and had a few nice bikes to try. I rode a specialized epic sworks, and a stuntjumper fsr comp carbon 6fattie. I had a lot more fun on the stuntjumper! According to this the ican p9 is pretty similar.
https://geometrygeeks.bike/compare/ican-p9-2017-m,specialized-stumpjumper-fsr-carbon-6fattie-2016-m/

I've ordered a P9 frame from Ican, as well as a 40mm wheelset which should all be here well before spring! I found a deal on a new rockshox monarch plus 210x60, and I'm about to pull the trigger on a 180mm dual position lyric. The frame geometry calls for a fork crown to axle of 571mm, the rockshox lyrik 180 is happily 572mm! I have noticed rideczech mention wanting a fork 20mm longer, when it comes available!

I've noticed most P9 builds I've seen seem to use shorter forks, in looking at forks for the past week I'm thinking this might just be because the market isn't there yet? I've searched a lot and can't find much I would like that has 110 front axle and fits 3" tires!! It's not easy finding options within my budget that are still available, then finding geometry and tire fitment specs is always hit or miss. I am open to suggestions, if you would like to share!

Would it make sense to use a dual position shock to have the option of ~1.33 deg steeper head angle on the fly or would a cheaper, simpler solo air be better? Is it a bad idea to run so much front shock travel? I think I would like the extra bb height, and if I understand correctly I need 571mm crown to axle to maintain 66 degree head angle as shown on the geometry drawing?

I plan on running GX eagle components, 165mm crankset. Is this the adapter I need for BSA?
https://www.ebay.com/itm/SRAM-Bottom-Bracket-GXP-Team-Cups-English-73-68mm-New/382257639479?epid=2254439874&hash=item590054b037:g:xcEAAOSwO7hZ6-5u

Thanks for reading, and for any and all advice!!

 

[Carbon_Dude]

I don't know anything about the P9, but I hope your build is as fun to ride as my SJ6F!  Good luck with your build!

[deezums]

Thanks, I hope everything I've picked works out alright in the end too!

I've been ordering parts and waiting for them to arrive for a while now, it's all finally showing up! I got the frame and wheels, they made it through shipping in excellent shape!



Here's a list of what I'll be running...

Ican P9 Medium frame
40mm ican carbon wheels with novatec hubs
Maxxis DHF/DHRII 2.8"
Rockshox Monarch plus RC3 210x60, 8x30mm upper bushing, 8x25.4mm lower
Rockshox Lyrik RCT3 180mm dual position
Reverb 125mm Post
Eagle GX groupset, 165mm GXP crank and 73mm adapter
Magura MT Trail Sport brakes, 203mm front/180mm rear
35mm stem, 740mm Ican riser bar

[deezums]

Most parts have come in! Still waiting on brakes, and some bleeding tools for the post...


https://s17.postimg.org/fy44dvxp9/IMG_20180120_190801.jpg


https://s17.postimg.org/5bab8ga4d/IMG_20180120_190709.jpg


https://s17.postimg.org/9kf1an88t/IMG_20180120_190745.jpg


https://s17.postimg.org/i2ohez71p/IMG_20180120_190721.jpg

Some notes on what's been done...

My steerer tube is weird looking, I am leaving it long for a while till I know how I want it permanently.

I taped up the Ican rims using Kapton tape, I ordered 35mm width and I had 20mm on hand from previous projects. The 20mm works much better as it's easier to pull tight with no wrinkles. The 35mm is perfect considering the drop center geometry (34mm inner width) but it's impossible to tension the drop center enough while keeping the bead surfaces flat and wrinkle free. No sealant yet and I can hold pressure for days with the 20mm tape, the tire is still easy enough to install and remove with no tools using the drop center. Partially mounting the bead by hand is all that's needed for seating the bead with an air pump. I am super happy with the wheels so far!

The routing for an internal dropper post is confusing, there are three outlet holes on the down tube as well as an inlet hole on the seat tube. At first glance it seems the routing is meant to go inside the down tube, out around the lower shock eye, then into the seat tube on the non-drive side. There is a hole inside the BB threaded shell, this makes it easy to run the internally routed dropper post internally the entire way with no aggressive bends and no worries on crank clearance to cables on the non-drive side. If the seat tube hole is an outlet for an external dropper post it's angled the wrong direction! I'm not really sure what's going on with the extra holes...

I found the chain length sizing kinda confusing, but I managed to work it all out using the bike itself. The chain growth is pretty radical with 60mm shock travel, keeping the chain short enough for full droop travel on the 10 cog while keeping a chain long enough at full compression on the 50 cog is tricky. These limits are pretty radical, not normal operating conditions by any means, but I managed to make it perfect. The lower chain guide I picked actually helps, it shortens the chain at full droop but does not do so as much at full compression. I'm not sure if this is the intended design, I didn't know it when I bought it but I like it! I am using 118 links on my chain, if this helps anyone else.

I also purchased Linakge software and modeled the frame as best I could using the given documents, hopefully they are at least to scale for this to be anything accurate. The most descriptive PDF does not give XY dimensions of piviot points, only direct dimensions in some places and no angles, useless!!


https://s17.postimg.org/b0vlpqp59/image.png

The following is a graph of anti-squat with 21-32. 50t is around 125% at 20% sag, and 215% on the 10t.

I wonder how well I can ride with no brakes?

 

[chetosmachine]

I have modeled the frame so let me know what dimensions you need. I based my drawings on the pdf plan from mtbr, they showed to be quite accurate. At least most measures where in the mm range proximity.

Your build makes me drool

[deezums]

Thanks! And thanks for the offer, if you've got a way to export a DXF or something similar I wouldn't mind taking a look! I believe I am +/-5mm or so right now, I used the more detailed Medium sided frame drawing and traced the piviot points and frame.

I'm in love with this bike already, the inaugural ride with no brakes went flawlessly besides me getting too confident in the mud! More like clay, that crap stuck! I locked the front wheel up on the fork but the rear has clearance for days! Wish the weather would cooperate more...

[chetosmachine]

I attach what I have, yours might be better as you can measure the real thing =)

For me it was just a quick work to see how I would fit.

I hope weather cooperates, you put brakes and make a nice review of the bike

Cheers

[Sitar_Ned]

wow this is really great info guys, thanks for sharing. Love the build.. super jealous! I don't need another bike!

[deezums]

Thank you both 

I'll compare the measurements you have with my own and see if there are any huge differences!

Water, water in the downtube!! There is no drain hole, I had to remove the bottom bracket! I need to check and see if any of the ISGC tapped holes go through into the frame, if they do maybe I can get a vented screw to use as a water drain. I really, really don't want to drill a hole anywhere! It seems an extra small hole could be placed in the aluminum BSA bracket pointing down, I will send a e-mail to Ican and see if they take suggestions...

Also, the wheels have taken on water! That's probably gonna get at the sticky side of my tape and ruin it!

Is this normal for carbon bits? To be fair, I'd call the amount of water I used cleaning mud about the same as throwing it in a lake. It's also unfair to call it mud, it was more clay 

I did a few things this evening, nothing too exciting. I took advantage of the Horst link and purchased some 50mm heat shrink and cut it into sections, then disassembled the rear pivots and slipped it over the chainstay for a ghetto chain guard! If you do this trick, I suggest shrinking the wheel and ground facing side before doing the outer and upper face as it seems to pull the heat shrink tighter with less heat and looks a little neater in the end. Lots of the heat shrink this size has glue included and takes much more heat to shrink, I wouldn't get that stuff!


https://s17.postimg.org/lz88ucan1/IMG_20180122_185229.jpg

I also bled the dropper post and I'm happy to report it works a lot more reliably than it did when I got it! It used to get ~1" of soft travel if you were to stop midway in the stroke occasionally, not very good. I haven't had that issue since the bleed, it only has ~1mm of vertical play. I am also glad I did not get a 150mm travel post, I would not be able to use the extra travel!

My brakes are still somewhere between the UK and USA, I may check the tracking number rather frequently 

More to come 

 

[lRaphl]

I really like your idea of heat shrink. Cleaner than anything I've seen so far.

[carbonazza]

...Water, water in the downtube!! There is no drain hole...
...Also, the wheels have taken on water!...

I drilled a 2mm hole, at the bottom of most of my frames when the water was not going out( there is mud half of the year here ).
Either because there was no drain hole, or it was misplaced due to the fork length.

For the wheels, I have a pair that takes more water than the others.
You can deflate and unscrew the valve when at the bottom, this will send the water in the tire.
Or just unbead one side of the tire to do it if it is a problem.
I've never noticed any issue with the tape though.

I didn't say it directly in this post, but it is an amazing looking bike 

[deezums]

I'm not sure I can bring myself to drill a hole, and I'm not too keen on pulling the bottom bracket apart often!

I believe I can figure a way to control a proper drill bit to do so without delamination, but not so much when crossing over into the aluminum. The aluminum bracket also has a 5mm lip inside where it meets the downtube, for complete drainage I would need to drill the downtube. This lip also makes it interesting getting dropper screws out of the frame, careful while removing those hose covers

I'm not sure what I would like to do, I'll have to think about it for a while. Maybe I can use a thicker version of plastidip to seal as much as I can? I wish the seatpost were a little easier to remove!

If I dry out my wheels and put a little sealant in with the nipples I wonder if it'll help keep that water out. I'm not as worried about the wheels as I am the bottom bracket.

Thank you both for the nice comments! Carbonazza, were the frames you drilled alloy or carbon?

[carbonazza]

Carbonazza, were the frames you drilled alloy or carbon?

Carbon frames... I know I shouldn't, but water and mud were accumulating regularly, killing the bearings quickly.
They are still riding ok, without cracks there.

Isn't there a hole in yours?
Maybe it is just misplaced because you have a fork that is longer or shorter than it was planned.
You could just make your bike stand with a wheel elevated, at the right angle so it empties itself.

[deezums]

I don't think this frame has a hole, I checked the iscg holes and they are blind so I can't use them as a drain. I might just have to drill one

My brakes finally came, tomorrow I might get some real riding in!

Bleeding brakes sucks! It took much longer than I thought it would, all the daylight was gone by the time I was done. In the end I made a hanging handlebar reservoir and used a syringe to push/pull fluid back and forth 800 times. I found it best to only trigger the brake lever while pulling fluid through the caliper, then waiting for all the tiny microscopic bubbles to collect on top of the syringe before pushing it back through. Also zip tied the calipers vertical and tapped them with a plastic handle a lot to dislodge bubbles. When I was finally done I capped off the master cylinder while using the caliper syringe to purge all air from the bleed port. I had to remove the calipers and make sure to have them above the master cylinder when removing the syringe from the caliper, then I'd use the syringe to add a few drips of fluid to the port before installing the cap. I'm pretty happy with how tight they are now, but I think I can make them better still.

I came up with a trick for the rear brake cable, there is no cable stay on the seat tube and the cable naturally wants to flex out into the crank arm. Since I did not use the odd extra dropper post hole I was able to use it and a zip tie to make a seat tube cable stay.



Here is a shot of the rear at full droop travel with the 210x60 shock, the seat sure gets close 



I took the bike out to some jumps earlier, while I still didn't have brakes. I tried sending it, but it's still pretty muddy and no brakes don't mix well. I ate it a few times and christened the pedals on my calves really well, but the bike took it all like a champ. I cased one pretty good too, used all but the last 10-15mm of the front shock but still managed to roll over. Whoops! 

The bottom bracket is really really low! It's going to take some getting used to, feels as though you'll hit everything. I got a pedal down hauling around a corner on a paved trail and skipped the rear out pretty good, could have went a lot worse.

I think I need to slow down before I really hurt myself 
 

[carbonazza]

Bleeding brakes sucks!

Only the first times