Rear rack for disc brakes
 

Looking for a heavy duty "open tubing" style of rack (not light weight voyager/blackburn platform-style) for a Specialized Globe San Francisco 2. Along with the clearance issue of rear disc, this frame has no eyelets on the drop outs. The seat/chainstays are split and attach with 2 allen head bolts, one of which is tapped & threaded - the only rear attachment point(pictured from chain side). Fenders will be mounted using this attachment.

I have found a rack on eBay that clamps to the lower seat stays (pictured) and wonder if anyone has experience with this type of rack or mounting? It looks very adjustable & sturdy - only drawback being many bolts to come loose with vibration and usage (loctite should fix this once it is properly fitted and positioned). Also seat stays are square tubing- possible clamping issue?

several Disc rear-racks use a QR skewer as the bottom mount .

with a bolt on hub the hole needs to be reamed out, to 10mm from the skewer diameter of 5mm ..

Have you asked the Specialized brand bike dealer, you got the bike from , what their typical solution is ,for this ?

Tubus Disco comes to mind immediately.

http://www.tubus.com/product.php?xn=10

super nice, super well built, but not so cheap, no good German products are.

http://bikeforums.net/attachment.php...hmentid=334818

Internal gear hub so skewer mount likely not the best idea. Prefer to leave rack mounting intact if wheel needs to come off.

Bought bike used - local Sec. dealer had never heard of this model - didn't recognize or know of the threaded allen head frame bolt - their only suggestion was a seatpost rack (which may not have the weight capacity I need and don't want quick release for security reasons)

Another solution might be machined standoff that would bolt onto the allen head frame bolt; providing extra width for clearance of the disc caliper and possibly two holes - one for the rack and one for fender.

Has anyone seen such an item? It would certainly open up selection locally for a rack and avoid buying "sight unseen" from China via eBay.

I will have access to the machine shop at school in a few weeks, this might a good project for a senior student.

To be honest, I've never a bike with IGH without the proper mounting hardware for fenders and a rack.

Very shoddy design if you ask me.

there is what going on with that bolt, that is the dropout slide ?

an arrangement where a bigger bolt is internally threaded for a Smaller bolt to fit in the hex

to tighten the larger bolt.. has been done before ..




IT seems to have removed the mechanical problem solving in youngsters. :50:

Considering the overall (advanced?) design of the bike: splittable rear stays for belt drive (which was available on the next model up), eyelets for upper rear rack mount, front fork eyelets on dropout and mid fork - perhaps the threaded allen heads were their solution for a lower rear attachment point. Specialized's niche marketing for the Globe line was to get people biking instead of driving - I think a few other Globe models came equipped with fenders, racks and even lights - If I had bought new in 2009 that would have been a good choice.

replace 1 bolt with a stud and 2 nuts, the lower nut will clamp the sliding dropout, as before..

the upper nut will hold the rack..

You use an allen wrench to hold the end of the stud , while you tighten the nuts..

That is the arrangement, but on the brake side the caliper would be in the way of a vertical rack support attached there. I'm also mounting full fenders and prefer a separate eyelet for the braces. Thought the threaded bolt heads would be perfect for fenders; if the lower rack mount could be attached to the frame.

Thought of P-Clamps for the rack, but again the stays are square tubing.

RIV_Nuts in the seatstay?

In short - I'm fine with mounting fender braces on the the threaded bolt heads - rack will not clear disc caliper if mounted there.

Your idea of the stud may work- one nut to lock frame; then attach fender brace, 2nd nut will secure fender brace & hopefully provide clearance for caliper; attach rack and secure with 3rd nut. A short tubular spacer or few washers may be needed for clearance on the brake side as well.

Prefer not, with the thin walled alloy stays and the weight that could accumulate on the rack. They're OK for bottle mounts and lighter applications on seat or down tubes.

Thanks fietsbob.
Definitely some good work arounds - gonna think on this a bit longer and do some searching on the web when I have spare time - before I hit the Buy-it-Now button on eBay.

The bike was bought to be be my winter/bad weather commuter so (hopefully) not be needed for at least 3 months.

so you also have Mudguard mounting to sort out, too.. Or maybe not, so snow won't pack up underneath them..


FWIW , hose whowork in Bike Shops , help customers figure out how to adapt-mountstuff

Ebay just takes your Dosh ,



and then people come here and complain about being ripped off at LBS

because their things are not as cheap as wally world.

Yes - Fenders/Mudguards and possibly a NuVinci rear hub (I think you were in on my thread a few weeks ago). I used Bontrager clip-ons on my mountain bike last year with no snow sticking or build up (by the time we get any amount of snow the temps are cold enough it doesn't stick). For winter, I'd liketo keep things simple. The fork has lots of clearance. Rear triangle is very small so clip-on will have to mount forward - may not give good coverage off back of tire - but that's solved with coroplast attached under the rear rack protruding rearward.

LBS here are 2 full line sporting goods stores- so they are busy with back-to-school, fall stock & in one store the bike accessory aisle has transformed to hockey gear already. On the bright side I can get a good deal on a rear rack there & can "eyeball" it against the bike for approximate fit.

Its still"a work in progress."

visited AB in January .. cold enough the moving van Bekins truck didn't need chains ..

going over the Sierras in California, they were mandatory at times..

bicycle , I'd still get studded tires since you wont have 4 wheels to hold you Up.

Studded tires for sure- likely Schwalbe.

read they shed studs if too new.. a rubber hardness issue ..

Read that too, rubber compound & inflation.
Schwalbe makes:
Snow Stud - 100 studs on alternate outside tread / low inflation (30-45lbs) Good all 'round recommendations
(My choice so far)

Ice Spiker - 304 studs on outside & center treads (40 - 65lbs) good for ICE

Extra studs - 12 for $9.95

I have the same rack(Axiom brand) on my commuter/errand bike....

http://www.universalcycles.com/shopp...s.php?id=63240

I use these with Schwalbe Big Apples 26x2.35 and Schwalbe Supermoto's 2.35....during winter I switch over to Schwalbe Icespiker Pro's 2.35"s for deep snow and ice, Nokians Mount and grounds for the rest

also have easy off fenders when needed and never any problems with tires or fenders

oh and just a suggestion, instead of the Schwalbe Snowstuds go with the marathon Winters for a fantastic all around tire for winter riding, slightly more studs, kevlar lining and not bad as far as rolling resitance....just inflate higher psi when on nicer days and lower psi when the conditions warrant..

I bought a set and will use them when my Nokians wear out....also read some bad reviews on the snow stud....

Glad to see the rack exists in reputable brand name - the one on eBay is likely a knock-off - any problem with any of the bolts loosening on it?

Thanks for the tire advice - I'm limited to about 26 x 1.9 or 2.0 by frame clearance. I've read that the Snow Stud works best at minimum inflation on mostly hard pack, with small a bit of ice (which is what most of our winter is)
BTW where are you from and what kind of temp/snow conditions do you get?

I installed it over 4 years ago, and nothing needed tightening on it and I've hauled some heavy loads...

I'm in Colorado and winter here is anything from full out blizzard to hardpack to slush....between the 2 sets I am able to handle everything....the good thing about CO is that it can blizzard one day and sun the next

also the Winters come in 1.75's which is what I have and also 2.00 and you inflate accordingly like the snow stud...high pressure for minimal ice and least resistance and low for snowy, iced conditions just like the snow stud...the added benefit is the Kevlar lining for flat protection

one other thing, whatever tire you get, make sure and break them in properly...it will pay off in the long run

Found the Axiom Odyssee rack online and ordered.
Thanks for the tip on Chain Reaction Cycles for the Studded Marathon Winters - great price with $9.99 shipping to Canada and they should out perform the Snow Stud tires.