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Messages - frankR

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1
29er / Re: Brakepads: 256SL XTR brakes
« on: July 18, 2015, 09:36:25 PM »
I have a med 256SL with XTR M9000 with 160mm Ashima rotors and my pads wear evenly.

 As 325racer said, remove spacer under the calipre mount if you have any. I'm guessing that's not the problem. In which case, this is a bizzare problem to have.

What size frame? Maybe there's a manurfacturing error on the caliper mount on your frame? Can you measure the distance between the calipre mount surface and axle center?

What axle are you running? 142x12mm thru or 135QR?

Some possible fixes:

Change dropout / RD hanger to move axle further from calpire mounting surface.

Contact iPlay for recommendations.

Chnage to 180mm rear rotor and add appropriate spacer under calipre.

2
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: June 12, 2015, 10:43:12 PM »
Once I figured out how the Rivnuts work I figured out how to use the tool. The instructions weren't that helpful.

What I discovered was iPlay never set the rivnuts in my frame. You could tell by how deeply recessed into the frame the threads were. These first few mm of the rivnut are designed to collapse as the rivnut is compressed against the plate it is inserted into. After I set the first one the bottle cage insert became rock solid.

There was only enough clearence to set three of the four rivnuts. The bottom one on the seat tube can't be accesses by the tool I bought. There is another way to set rivnut using a screw, nut, and star washer to prevent the rivnut from rotating in the hole. I will get it later.

Astro Pneumatic Tool 1427 Hand Rivet Nut Kit https://www.amazon.com/dp/B004KLVJAA/ref=cm_sw_r_awd_Kt6EvbQ0F0GCH

Edit: It appears what I thought was cable slap was really the loose Rivnuts. Bike is now relatively quiet.

3
I run 2015 Specialized Roval Control SL. 22mm inner width hookless (specialized was the first to market on beadhook-less carbon rims if I am not mistaken). They are similar spec to the light bicycle wheels.

Currently I hVe mounted  Maxxis Ikon 2.35 F/R 19/21psi with Stans. Awesome setup. Great all around performance: light weight, fast rolling, compliant/comfortable, and excellent traction. A little loose on some trails but all I need for 99% of what I ride.

I love the beadhookless design. Strong and low weight. Slightly more difficult to mount tires. The RaRa 2.25 I was running before were a challenge to mount. The Ikons are relatively easy.

I think its obvious wider beadhookless rims run tubeless are the way to go.

4
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: May 30, 2015, 03:51:02 PM »
Update to my update:

Vipassana,

Thanks for the tip on the rivnuts. I ordered a tool from amazon and m5 inserts. Will try crimping in new rivnuts. Right now I am running only one bottle cage. That's not going to work in a race.

A cure for the frame creaking has remained elusive... I have tried synthetic axle grease and silicone grease. None have worked. My next thing to try is some kind of elastomer. I did fix the creaking BB bearing. See photo below. One bearing was nearly frozen. Not surprising since I found enough dirt in there to host a reasonably sized flower bed.

I have tried several cable slap fixes. They all work for a time but eventually shift around and I end up with slap. A deadened slap, but still a slap.

Last weekend I installed new brake pads, SwissStop Sintered. The Disc E pads worked great until I burned through them. The rear pad was nearly completely gone. I have been riding with very little braking power the past few weeks. The Sintered pads have phenomenal power. I am now loving the XTRs again.

Unfortunately, during that first ride with new pads I had a little crash and that crash somehow pushed the front brake lever all the way forward, ejecting the snap ring out of its groove which holds the piston that applies pressure to the master cylinder. The brakes still worked, the lever just wouldn't return to it relaxed position flipping several inches forward when released. I thought the lever was toast since I couldn't find any repair instructions on the web. After digging into the mechanics of the mechanism the repair was completed rather quickly using a pair of snap ring pliers, after draining the system of fluid. A quick bleed and they were good as new.

I am still on course to buy the Niner AIR 9 RDO, but I am likely to wait for the right deal to come along. The frame retails for $2k. I would like to find a close out or new frame purchased second hand locally. There's a 2015 frame for sale on Craiglist for $1300, I would buy it but unfortunately, it's an XL.

Regarding the alleged conspiracy among bike manufactures to sucker us cyclists out of our hard money through continual revisions to "standards" and geometry, I say, you might have a point, but it's really a myopic allegation, IMO.

No one forces you to pay full retail every year to buy the latest and greatest gear. Great deals can be found buying closeouts on last years gear or prior generation components. If you are resourceful there are great deals to be found on state of the art gear. The reason why bikes have become so good over the past two decade, MtBs in particular, is through the hard efforts of the big name bike manufactures. Effort which requires tremendous capital which must be recuperated. Yes their business models demands they must continuously evolve and innovate. Specialized moto is "Innovate or Die". I think that credo applies to all bike companies. It's a highly competitive market. To stay in business you must push at the margins of technology. And yes sometimes that means changing standards. Consumers vote with their wallets. I refuse to take the cynical view by dismissing it as change for the sake of change.

The reason why relatively inexpensive Chinese frames exist is because of the hard work done by the name brand bike manufactures. I have yet to find any Chinese bike manufacture producing original innovative designs. They are blatant copies of existing bikes. Hence their low cost, since they have little R&D to recoup, and low overhead, and cheap labor, and can skimp on quality control.

Ultimately, I say ride what you want. Build what you want. But don't hate on the name brands because they are the source of the great equipment we get to enjoy, either directly or indirectly.


Photos of mentioned mechanical repairs and racing photos of the 256-SL in action included below.










5
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: May 19, 2015, 10:28:55 AM »
7. Will likely replace with Niner Air 9 RDO frame later this year.

Just curious. Why wouldn't you stick with the 256?

Good question.

My original intent was to ride the IP256SL until the new Niner Air 9 RDO frame became available.

Motivation to go from the 256 to the Niner is I suspect it's a better frame through a better optimized carbon fiber layup: stiffer and compliant where it needs to be. Though I can't say for certain without riding the two frame back to back.

Also, I am generally pleased with the 256SL, but there are some issues:

1. Creaking rear dropout / through axle
2. Loose bottle cage inserts
3. Cable slap
4. User unfriendly internally routed rear brake line

If I can address the above issues I may ride the frame longer, at least until the end of the season.


6
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: May 17, 2015, 03:44:38 PM »
Update:
750 hard trail miles on the bike. About 200,000 ft climbed.

1. Completed several races on the IP-256SL and very pleased with the performance of the bike
2. Have yet to completely eliminate cable slap
3. A little diappointed with the power of the XTR 9000 brakes. I think poor bleed is part of the issue.
4. Bottle cage inserts loose. Trying a repair with super glue (not optimistic)
5. Rear drop out creaking. Just tried removing from frame and greasing. Hopefully that cures this.
6. Overall durability and quality of the frame is generally good
7. Will likely replace with Niner Air 9 RDO frame later this year.

7
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 30, 2014, 12:32:25 PM »
25,000 feet climbed on the 256SL last week. Rock solid so far.

Anti-cableslap needs work... Other than that, no complaints.


8
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 30, 2014, 12:26:27 PM »
AbsoluteBLACK monolithic chainring installed. Went on in less than 5min. As for the claimed weight savings...

This is proper exaggeration!

"These chainrings save more than 150g over the regular spider and chainring combo."

375% less weight savings than claimed.

Not surprised. 150g sounded far-fetched. They must make this claim based on a low-end SRAM 3x crank, with tungsten chainrings, and uranium bolts.

Update: After one ride these rings work great. Marginally stiffer. The XX1 crank was already very stiff so not much room for improvement. It does change the look of the bike quite a bit. Cleaner, more business oriented, form following function compared to the SRAM rings.

With only 40g saved compared to stock XX1, not sure it's worth the investment for most folks.


9
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 28, 2014, 10:30:22 AM »
Race season begins on the road bike with a hill climb on New Years Day next Thursday. First MtB race is Jan 18th. Most of my races this spring will be road races on the road bike.

Not sure how the two piece design would aid heat dissipation. However, it likely does aid in durability by mitigating bending / warping.

10
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 25, 2014, 02:47:41 PM »
That is heavy and disappointing as a % that is way off...your bolts aren't titanium are they?
My Quaxar discs were 69g for 160mm and 7g for the 6 bolts(titanium)
Your not talking about Shimano ice tech rt98 then - 140mm ice tech is 91g w/o bolts
Nice tip about the crank and bb.

No bolts are not Ti. I think Quaxar gets lower weights with a two piece design. The friction surface looks identical to the Ashima rotors. I suspect Quaxar modifies them to obtain the lower mass two-piece design.

My Shimano rotors are XT SM-RT86 Rotor - 6-Bolt. Glad to hear you liked the crank tip.

Two-piece Quaxar design. I've seen several styles of this design. These are available on eBay for $38 a piece. Saves 14g over the Ashima.


11
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 25, 2014, 02:17:36 PM »
Unfortunately my instincts were correct regarding the Shimano rotors being glazed. This past Tuesday afternoon was my first ride on the 256SL following the harsh Miwok decent back in late November. Towards the end of that descent my brakes started to fade. Immediately I suspected they were glazed. On my first descent Tuesday I had zero braking power and the rotors were howling frighteningly loud.

My attempt to restore the Shimano rotor surfaces with sandpaper followed by a systematic break-in process was a disappointing failure. Brakes were oscillating and howling with no power.

I can only suspect the Shimano compound does not hold-up well to high heat. Even when operating at peak performance I was not impressed with the breaking power of the Shimano pads.

So this meant the new Ashima rotors went on along with the new SwissStop Disc "e" pads...

After following the bed-in process described below, I am extremely impressed with the Ashima rotor and SwissStop pad combo. Great power and modulation. The XTR brakes are beginning to live up to the high expectations I had for them. If this result holds up, these Ashima rotors are among the best value I have ever come across in road or MtB components, considering they can be bought right now on eBay for $28/pr!

The bed-in process:

No doubt there are many different methods by which one can "bed-in" a fresh set of brake rotor. Below I describe one such process that has worked for me in the past.

I start by riding on flat ground dragging the front or rear brake lightly to build up heat on the disk and pads while not allowing the rotors to make any noise (the dreaded squeal). After a minute or so of this when I feel the rotors begin to bite I do a couple of hard'ish braking runs from ~20MPH coming to a near stop, but not to a complete stop. It is critical you do not allow the brakes to make any noise or oscillate! This will cause uneven bed-in and that pattern that causing noise/oscillation will bed into the rotors surface and you may ruin your rotors. If the brakes make noise, brake harder and harder until it stops. I repeat the above process for the front and rear brakes independently. If your legs are burning and your breathing hard you've done it right. You need some heat to transfer resin and friction compound to the rotor surface.

After about 5 of these braking runs I stop and remove the pads from the calipers for inspection. As the pad compound goes through a thermal cycling it will look blackened, see photo below. Curiously, I noticed on the SwissStop pads that only the center of the pads were black and the perimeter looked like new compound. This is a problem since it will not promote even "bed-in" of the rotor surface. To correct this I lapped the surface of each pads with 120 grit sandpaper on a smooth workbench surface. Only a few seconds of a circular grinding pattern are required to remove the blacken layer and expose fresh compound and flatten the pad surface.

The pads then go back into the calipers, being careful not to contaminate them during this whole process and I repeat the same bed-in process of dragging the brakes followed by hard'ish braking runs. If you're doing this on asphalt/concrete make sure you use old tires because rapid acceleration/deceleration will quickly chew through your tires. I then head out on to a ride with a steep hill to complete the bed-in process. Yesterday I had a 2500 foot climb averaging about 10 percent grade. On the descent, I don't allow the bike speed to exceed much over 25 MPH and I brake both the front and rear as evenly as possible without allowing the wheels to lock, which the rear is prone to easily locking, especially if you have a heavily worn treadles bald rear like I do!

That should complete the bed in process. However, I am going to avoid any high heat descents (like Miwok) for a few rides to let the brake bed set-in (playing it cautious).

Pads and rotors following bed-in yesterday:


12
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 25, 2014, 01:50:00 PM »
Glad I rode the new machine as much as I could back in November because my area of Northern California has seen well over one foot of desperately needed rain over the past several weeks. On the downside this caused a month long hiatus in riding the new chiner. The SJ has substituted on a couple muddy rides over this time.

Upgrades:

- Extralite grips installed. Love'em so far!
- Ashima rotors + SwissStop Disc e Pads (more on this in next post)
- Chinese $20 carbon bottle cages. Garbage! Trash can.

Mixed results with the cable slap mod. By and large cable slap is gone. I only hear it on the biggest hits or drops. I am content with how things are for now.

From one extreme to another, the once parched Northern California hills are now sodden and glowing green with luscious grass providing hopes of the record breaking California drought subsiding.

13
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 06, 2014, 01:06:58 PM »
Ashima rotors arrived in the mail today (same as Quaxar as far as I can tell). Purchased direct from Taiwan off of eBay.

Weigh in well over the advertised (66g) at 86g. That's a 30% difference! Without screws they are 74g (12% difference).

Delta weight compared to Shimano is 78g (including screws).

1.80mm thickness. Surface grinding looks good. Same thickness as Shimano "Ice Tech" rotors.

Purchased SwissStop Disc 28 e. The "e" representing "electric bike". These had the highest average rating on SwissStop website for power, modulation, and wear rate. Figured I would try them. Running the standard sintered SwissStop pads on my Formula Brakes on the SJ, which I have been pleased with. These "e" pads also appear to be a sintered compound, impregnated with something (green stuff?)




14
29er / Re: IP-256SL XC Racer Build 18.5lb
« on: December 06, 2014, 12:50:00 PM »
Do you have a gxp or a bb30 xx1 crank? If Its a gxp, how was your installation? Did you use Any spacers? And witch bb set dit you install?

BB30. No spacers. Wave washer only.

Wheels Manufacturing Enduro angular contact bearings with SRAM BB30 bottom bracket kit (needed for wave washer and dust covers).

Install was "easy".... Actually, if aiming for perfection, I find nothing "easy" about working on bikes, including installing BB30 bearings and crankset. I imagine if you are a professional bike mechanic, i.e. work on bikes for a living and have installed press fit BB30 bearings 100s of times, it becomes "easy". Like anything else, once you becomes practiced it becomes easier. Contrast that with what you read on the internet...

To press the bearings in I used BB30 dies that came with a Park Tool kit. I also bought a press off eBay, which consists of nothing more then a threaded rod and pair of nuts and "precision machined" dies. Unfortunately, I found the precision machined dies too well machined. They fit extremely tight in the ID of the BB30 bearings. Even heavily lubed, I press fit the dies to the bearings instead of the bearings to the BB30 shell. So I substituted in the "lower precision" Park Tool dies. Even so I found the shell very loose, and pulled out the ND side bearings when removing the crank. This suggests the ID of the Wheels Mfg. bearings are tight fitting and the IPlay shell is comparatively loose.

Pay attention to how you pre-load the bearings. If you immediately torque down the crank bolt to spec. I found you will impart an eccentricity to the crank, and it will visible spin "untrue". The correct procedure I found was to spin the crank in the bearings as you gradually apply torque so the bearings in the race can center themselves. I have found this to be less of an issue with GXP style BB.

The crank is working flawlessly, so far, after only 3 rides. No dreaded BB30 creak. Very stiff and smooth.

15
29er / Re: IP-256SL questions.
« on: December 06, 2014, 10:53:12 AM »
Can't you just put a 32 on the front and go with smaller rings on the cassette to get the same ratios?  Plus it would shave off about 5 g :)

Smaller than 10t? ;)

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