Saturday, June 21, 2008

Testing one two...

Although at times it can be a bit over the top when the rest of my life is chaotic, most days I feel pretty fortunate to have frequent opportunities to evaluate prototype bike stuff. I divested myself of a few of my eval relationships the past few years in order to get things back to a more manageable level, and lately I've really, really been enjoying the process.

It's fascinating to be a part of the ground-up process on some of these parts/tires/suspension/frames, etc... because you get to start with a vision and move concurrently through protoyping, pre-production, testing/eval, tweaking, re-production, more eval and tweaking, then finally production. In some cases that process takes 2+ years start to finish. Patience is required and is far preferred to rushing then roundfiling a design and starting all over.

While much time is spent verbally sharing or emailing ideas and suggestions in both directions, it's necessary to actually ride the product in order to be able to discuss improvements. Currently the LunchBox has more pre-production or proto parts than it does production stuff, but its been that way for several months more-or-less untouched so last night I added a new variable: A fresh off the boat set of proto FR/DH tires. John swung by on his way home from work and picked up one of the samples to install on his Behemoth, then we met for a ride early AM today.

And what a fantastic ride it was.


When testing I prefer to ride solo so that I can pay attention to whatever it is that needs evaluating--at least for the first ride or two. Once I have a decent handle on the performance and a few of the variables it's fun to share the love and stick one of the proto parts onto someone else's bike to get their take on things. I'd ridden the new tires for ~3 hours last night on one of the better test tracks available on this planet, then John and I rode out and duplicated some of that loop this morning.

For normal human beings like us, climbing a 36lb pig isn't exactly "fun" per se, but there are so many things to enjoy (like gorgeous morning light on the way up) that the climbs go pretty fast and little blood is shed.


First few chunky moves off the top.




We stopped and chatted several times on the ride, mostly discussing the tires we were riding. This tire has a reasonable chance of being produced and shipped quickly, so our riding and discussion today focused on tread pattern, apparent casing durability, and tread compound. Precious little scientific terminology was bandied about--it was more along the lines of 'Holy shit--did you see THAT?!' or 'WOW--I can't believe I got away with that one!'

John biting off a bit more than he had bargained for.


A heady move that I don't care too much for. John snapped this one a bit early but you can clearly see the dark flat ledge that my front wheel is about to clear. The front wheel doesn't touch it but even if you 'ride light' the back slams pretty hard. On a normal (non-tire-testing) day I'd unweight the rear end as I slammed into it to keep from flatting or denting the rim.Today I sat back and kept my full weight planted on that sucker. Harsh noise and a minor dent but no flat. Time to start dropping the pressure. We'd both started at ~20psi but it was time to see how low we could go.

A hard rear wheel slam on this manual, followed by an off-camber hole that really torques the rear end of the bike around. On an XC bike this move is borderline painful (and is probably gonna take years off the life of the bike) but today, at ~10psi, it was disappointingly smooth.


I shot this one a touch late of John clearing some chunk, but I like the way you can see how packed up his rear shock is. Using all the travel.


Still hadn't been able to flat 'em despite several (deliberate) badly chosen lines. So we dropped the pressure even more--I didn't have a gauge with me but I guessed that I was at ~5 or 6psi at this point.


Very few people would want to run these pressures because the wheels become a lot harder to push and a lot less predictable even as traction goes through the roof. The tires just conform to every rock of any size and as long as you can keep the power on you *will* maintain traction.


Manualing/dropping to flat at stupid low pressures.


Our bikes are set up very different so we swapped for a bit to compare and note differences.


John noticing a little 'float' from the low pressure rubber on off-camber rock.


I noticed a mechanical issue on John's bike that required immediate attention. We were both impressed that he still had *one* chainring bolt hanging on, and that the other three only needed an average of 8 turns to snug 'em up.


Lots of dust on rock and kitty litter on hardpack on the local loops--pretty typical for summer. We were both impressed to the point of surprise at the lean angles we were able to achieve and the lack of drifting we experienced in these conditions.


My turn to use up all the travel.


The in-run to this one is slightly uphill, then you're pointed down when it comes time to manual off. In short, it's almost always a hard hit. John makes it look smooth anyway.


What goes up...


Must come down.


Sometimes again and again because it's such a fun one.


Back into the chunk.


Arcing it in prep for a fun descent.


Testing the tires' braking capabilities in ball bearings.




The ride was only ~2 hours long but we learned bunches about this personality of this particular tire and now have some solid feedback to offer to the manufacturer. I'm not big on working weekends but sometimes, like today, I'm willing to take one for the team to keep the process moving...

There are worse ways to spend a morning.

MC

P.S. I was wrong on the pressure I had settled on--when I got home and checked it with a gauge the rear tire pressure didn't register. I'm thinking it was more like 3-4psi...

Thursday, June 19, 2008

The Process.

Building wheels is undeniably my bread and butter but a few times a year I build bikes from the ground up. It starts with an email (or, in this very rare case, a phone call) and many conversations are had before the first components are ordered.

I don't cater to the instant gratification crowd, mostly because the frames I build are always in high demand (read: it sometimes takes weeks or months to get them) but also because my time is in high demand. Someone wanting a bike right now is gonna be pretty frustrated when it takes me a day-and-a-half just to research the details to answer their questions.

But for those willing to wait the process is worthwhile--for all involved.

In this instance the customer is a 5'5" woman that weighs ~135# all geared up. She's been riding most of her adult life but has been away from MTB's for many moons. A demo day in Moab gave her a pretty clear picture of what she wanted and didn't want, and with a little education and a little time I was able to get crystal clear clarification on every last detail.

This part of the process can be time consuming, but walking someone through every component choice (and often walking them through how each component relates to and affects the others) is also rewarding, especially when they're paying attention and really care about the end result. They ought to care--it's their bike!

A size small 3" travel LenzSport Leviathan was decided on. One phone call to Devin Lenz and 3 days later the frame was here. It hung in the rafters for a few days while I cleared my wheel order backlog and built the wheels for it.

I start by weighing the frame, mostly because many, many customers ask what the nekkid chassis comes in at: 4.73# for this one. I've owned *many* heavier hardtails!

Clean and lube the seat tube then install the seatpost so I can hang it in the stand.

As the components arrive I keep them separated in a box so that (at a glance) I can verify that I have what I need without getting confused by general inventory on a shelf.

The only other item I weighed on this build was the rear shock. Amazing where bike technology has gone the past few years: A carbon fiber rear damper with external rebound and lockout adjustment, all at 138g. Why would you ride a hardtail anymore???!

Devin chases and faces the frames before shipping 'em, so all I need to do at the BB is run a thick rag through the threads to remove any metal chips or blasting media. All clean here.

You can use a fancy-schmancy high dollar grease if you want, but I don't really see the point. I use the same stuff on my bikes and my customer's bikes: boat trailer grease from the local hardware. All it's gotta do is keep the BB from seizing in the frame and it does that as well as anything available.

BB cups threaded 100% of the way in by hand, then I torqued 'em with the wrench. Smoove.

Slip the drive-side crank through, attach the non-drive to it, then spin the wrench a few times to snug it before torquing. Very slick setup.

While you're down there (and you have the boat trailer grease handy) might as well spin the pedals on and torque 'em.

I use the same thick rag to remove any dust or grit from the inside of the head tube.

Lube the head tube then push the cups in nice and smooth.

There's so much dust flying when I cut the steerer that I kept the camera put away. Not knowing exactly where the bar height will end up on this build I left ~20mm of extra steerer to work with. In the unlikely event that they're needed I also have 6 different stems (in 5mm increments and 7 or 17* rise) so that the reach can be 100% dialed before she takes her new baby home. Here I'm torquing the stem pinch bolts to 5.2 NM.

Same torque spec is called out for the bar pinch bolts. The torque wrench is so easy to use and parts are getting so light that I see no good reason *not* to use it.

Top secret grip glue.

Running in the rotor bolts.

The wheels were built two days prior and that process is the subject of an entire post. Someday...

Installing the tubeless tires and inflating them is easy cheesy, although I did it start-to-finish without grabbing the camera. Guess I'll have to dedicate a post to that too...

Installing the cassette.

Just a matter of spinning a 4 or 5mm wrench a few times to get the shifters, levers, saddle, and derailleurs installed. Slip the wheels in and tighten the QR's--it's starting to look like a bike.

Bolting on the brake calipers.

Running the rear brake housing through under-the-downtube p-clamps. There are cable stops on the top tube that the brake line can run through, but I prefer this method as it's cleaner, quieter, and better sealed.

'Round about this time of day the temp in the shop hits ~102. Union rules require me to two fist 'em at 100+.

Phew--close one! None of that icky stuff in here.

Install the chain with a quick-link. Doesn't get any easier.

I lube the chain immediately so that the lube can soak in while I'm running the cables and tidying up. Best to have a lube-soaked chain when adjusting the shifting.

Once slack is removed it's time to cut the cables.

Limit screws are set, cables are stretched and retightened, then cable tension is fine tuned.

End result?

It's a bike!

I call the component assortment on this build 'sensi-bling'. It is a high-dollar build but nowhere near no-expenses spared. Take the shifters and derailleurs for example--SRAM X.9 is top-notch, solid, dependable stuff that doesn't cost an arm and a leg. You could spend a heap more on X.0 but would you notice the negligible weight loss or any increase in performance? I can't tell a difference from X.9 to X.0 on the scale or on the trail, so I simply don't see the point in spending the extra $$$.

Likewise with the brake levers--Avid makes a lever set that is three times as expensive as this one. Know what else? That ultra-bling lever set is heavier than the levers pictured here.

Bontrager makes far, far more expensive stems, but they don't make any lighter than this one.


There are places on the bike where spending a little extra dough *does* indeed get you noticeable weight loss or performance gains. I'm a big fan of DT Swiss componentry. The shocks are light and durable, with a failsafe mode so that in the highly unlikely event of air loss you can flip the lockout lever and get yourself back home without compromised geometry.







After a few laps around the back yard to fine tune a bit, I tooled up and down the street and fine tuned it some more. At this point the heat of the day had started to slide back south of 100 degrees so it was time for me to trade the work boots for cycling shoes and head out on a ride.

Last step in the initial build process--recycle all the manuals, boxes, and packing material. My shop is waaaaaaay too small for clutter--everything has to be in its place or it ain't possible to move around.

Before the customer comes to pick this bike up next week I'll have ridden it a total of about 10 miles, mostly on an urban loop that I've found works really well at burning in the brakes and dialing in the suspension and shifting. When she walks through the shop door the bike might possibly have a few specks of dust on it but it will most assuredly be 100% debugged and trail ready, and I think just about anyone can appreciate that.

So that's how it works. Who's next?!

MC