QX100 early review

[Gunnstein]

I finally got the spokes I ordered, so I could finish the 406 wheelbuild:

So this is how a QX100 looks with wide 406 BMX rims and fat-ish tires. 55 mm on the unsuspended front, 47 mm rear. 32h hubs, rear is an SP dynamo and front is XT. The front tire clears the fork with about 5 mm to spare on either side.

Bummer: The rear derailer rubs the tire when on the largest sprocket. Seems I'll have to get a medium-cage derailer, which will limit the gears I can use. Hopefully not a problem - even now the front derailer/chainring combination limits gearing somewhat.

 

[super slim]

Check that the hanger bracket is straight in the vertical and horizontal planes, using a tool like this !
http://www.parktool.com/blog/repair-help/rear-derailleur-hanger-alignment

Or take it to a LBS.

If the hanger is straight, then add a 1.5 mm spacer washer to the inside of the cassette, to create more clearance, as I think you need a long cage to handle the front chairings.

 

[Gunnstein]

Thanks Slim! The hanger is straight, as far as I can tell. When seen from directly above, the largest sprocket is exactly flush with the side of the tire, so the derailer will have to be a few mm "inside" the tire. (The wheel dish is correct, it's just that the wide rim/tire combo ends up being 57 mm wide.)

As far as I can measure this, with a medium cage and a longer BB spindle (+4.5 mm q-factor) the chain and derailer will both clear the tire. A separate problem is the chain rubbing the large ring when on the middle ring and smallest cogs. It turns out the current crank setup is 2-3 mm short of standard 47 mm chainline. Moving the cassette out would make that worse.

With the current long cage setup I can use every gear except the small-small combo. With a medium, if I calculate correctly, I can still use the 4 largest sprockets with the granny, and that's enough.

Failing all that I can always fall back to a narrower tire, but am loath to do that since I want to maximise tire suspension. We'll see. It's a learning experience for sure.

 

[super slim]

If you have an old 10 speed rear cassette then you could use the 2.35 mm thick sprocket spacer, between the largest sprocket and the freewheel.

The chainline for the centre Chainring of a MTB (135 mm hub) should be 50 mm, instead of 45 mm for a Road triple (130 mm hub).
If the Bottom bracket is a square drive, then it should have a 118 mm long square drive shaft (MTB), instead of a 113 mm shaft (Road)
http://sheldonbrown.com/chainline.html

 

[Gunnstein]

The chainline for the centre Chainring of a MTB (135 mm hub) should be 50 mm, instead of 45 mm for a Road triple (130 mm hub).
If the Bottom bracket is a square drive, then it should have a 118 mm long square drive shaft (MTB), instead of a 113 mm shaft (Road)

I have already replaced the stock 113 mm BB spindle with a 118 mm, and the chainline is now 45-46 mm (q-factor 168 mm). So I guess my road triple is a bit narrower than the norm. I'll order both 122.5 and 127.5 mm BBs and use the smallest one that works, meaning a chainline of either 47-48 or 50-51 mm. I'll get a cassette spacer too, to use if required. Thanks again!

 

[Gunnstein]

First ride with the new wheels, my first homemade wheelset, and they didn't buckle during those 15 minutes. And no spoke pings. May the trend continue.

I started with 4 bar on the fat front tire (the max rating) which is way overkill. Then took it down to about 1.6 (minimum rating is 2) and that was still plenty, not much sag at all and quite comfy. The width is 1.5 mm less at that pressure, so there's a tiny bit more chain clearance.

The custom triple shifted a bit better "in real life" than on the stand, another plus.

 

[super slim]

What is the minimum seat height without the seat cushion?
That fold-able rear rack looks very stable!
Is it?

 

[Tom Bastnagel]

I just had my first session with my QX100 last night. Went really well except I noticed a pinging or creaking noise occasionally. Hard to discern between it being the shock or the spokes. Upon feeling around, loose spokes... Didn't check for finger tight nipples but they all felt real mushy. Tension is lower than any of the other 3 bikes in the garage. I used to build my own wheels (30 years ago!). Does a quarter turn on each spoke sound like a potential cure? I'd true it up a bit after that.

So my LBS tested the tension which seemed OK on the rear wheel. The front wheel was below standard and the dish was out. He tightened and dished the wheel further. Now no noise!

 

[Gunnstein]

What is the minimum seat height without the seat cushion?

51 cm, unloaded (no sag).

That fold-able rear rack looks very stable!
Is it?

I haven't tested it with a touring load, but just from trying to abuse it is seems as stable as you could possibly hope for given the frame attachment points it uses. Very solid up-and-down, maybe 1 cm side-to-side movement. They've built in a huge margin of error - the lower "wings" are 22.5 cm apart, so it seems impossible for the wheel or a fender to strike the rack or luggage.

 

[Gunnstein]

I got the dynamo lights set up. This is the Luxos U which has USB charging output. Good to keep the Garmin going on long rides.

I could route the taillight cable inside the rack, thanks to the welding holes.

 

[super slim]

Thanks! That is 100 mm lower than my Quest V1.0 with 26"*1.3" tyres!!!

 

[Gunnstein]

Since I hope to tour Japan on this rig, I've added an essential component for that:


Important part for touring Japan by gunnsteinlye, on Flickr

I'm using Star Wars Lego as figureheads on my bikes. The Azub has a Stormtrooper because it's black and white, brutish, and will go wherever you order it to go. The fatbike has a Snowtrooper, obviously (Jabba the Hutt was a tad too much).

The QX100 has Yoda, because it's also small, green, surprisingly capable, and somewhat "backwards" (front wheel drive).

Backwards, I speak. Annoying it is. Yes...


Yoda, my copilot is by gunnsteinlye, on Flickr

 

[Gunnstein]

As far as I can measure this, with a medium cage and a longer BB spindle (+4.5 mm q-factor) the chain and derailer will both clear the tire. A separate problem is the chain rubbing the large ring when on the middle ring and smallest cogs. It turns out the current crank setup is 2-3 mm short of standard 47 mm chainline. Moving the cassette out would make that worse.

With the current long cage setup I can use every gear except the small-small combo. With a medium, if I calculate correctly, I can still use the 4 largest sprockets with the granny, and that's enough.

I've switched to a medium cage X7 now, and swapped the 118 mm spindle for a 122.5 mm. Both chain and derailer clear the tire with a few mm, so I think we're good. I can actually use the 5 largest sprockets with the granny, so I have only lost 3 gears by going from long to medium (gears I wouldn't use, anyway).


X7 medium cage derailer with added protector by gunnsteinlye, on Flickr

 

[Gunnstein]

Current iteration:
- Added fenders, "SKS Velo 55 Kids"
- Added twin front bottle mounts, "SKS Bottle Cage Adapter" with "Elite Custom Race" bottle cages. The behind the seat cages will be unreachable if I use the Radical Design seat bags on tour.
- X7 medium cage derailer
- Shortened the kickstand to fit


Added fenders and front bottle cages by gunnsteinlye, on Flickr

Now if only the roads were ice free... at least there is an indoor parking lot I can use for basic testing.

 

[Gunnstein]

Some tricks were needed to mount the small fenders. In the front I used a Problem Solvers Fender Flute to bring the fender closer to the tire. I had to "sharpen" the top a bit to make it fit inside the narrow steerer tube.


Problem Solvers Fender Flute by gunnsteinlye, on Flickr

In the back I made a mount from a stainless steel ruler. You newer know, might need to measure something while on tour


Rear fender mount made from stainless steel ruler by gunnsteinlye, on Flickr

 

[Gunnstein]

The X7 medium cage derailer, with protector added because I've accidentally kicked it a few times. The medium is too short to rub the tire.


X7 medium cage derailer by gunnsteinlye, on Flickr

On that note, does anyone know which derailer hanger is used on the QX100? Is it a common model? Would be good to bring a spare on tour.

 

[tiltmaniac]

You could replace the 11-t idler at outer (lower) part of the derailleur with a 13t or perhaps (maybe, not sure) 15t idler.
I did this on my long-cage to get a couple of additional teeth worth of capacity. It may get you some gears back.
As a bonus, it also reduces the chances that the chain does something weird down there by disallowing the chain to jump off.

That'd put its length a bit between the medium and long... call it medium-plus

 

[super slim]

The Quest V1.0 has a standard H6 hanger.
Take yours off, to a LBS and buy a spare

 

[Gunnstein]

The Quest V1.0 has a standard H6 hanger.
Take yours off, to a LBS and buy a spare

It seems the QX100 is still using the H6.


QX100 derailer hanger H6 by gunnsteinlye, on Flickr

 

[super slim]

Its good to see, when on a good thing, stick to it!