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-   -   Specialized Stumpjumper 69er Rigid Commuter Conversion Gets REAL Fenders :-) (

joejeweler 03-07-13 10:36 AM

Specialized Stumpjumper 69er Rigid Commuter Conversion Gets REAL Fenders :-)
I wasn't sure if i should post this in the commuter forum, but thought the die hard Mountain Bikers might find some of this useful also,....IF, like me,'re tired of having to clean the slop off you and your bike from just a little rain.

I'm using my 2008 or so Specialized Stumpjumper (M5 Alloy), with a customized Surly Long Haul Trucker Fork w/disc tabs added. (It was already powder coated to match the blue on my frame) The front was pretty easy and straightforward with the braze on's and crown drilling already there. If you're running the usual suspension fork, you'll have to kit the usual suspension fork fender that helps some but leaves a lot of slop still getting through.

However, dealing with the rear of the bike the things i did should work much better, and is rock solid! As i'm using this rigid 69'er conversion as a commuter, i went with 45mm fenders from Planet Bike,....their "Cascadia" model with the stainless steel hardware and rubber mudflaps. They cover plenty for my needs using a Serfas Drifter 1.50x26 rear and a Michelin "City" 38x700c up front,......virtually the same width as the rear tire.

I found that using an altered 700c 45mm width fender worked great in this application, but see no reason a wider fender wouldn't work if you're running 2.00x26 rear. The larger diameter 700 wheel size fender looks "right", because it is positioned far outside against the rear triangle members.

Here's what i did........

joejeweler 03-07-13 10:37 AM

For a clamp onto the seat stays, i picked up a few 3/4" clamps with the protective vinyl covering and some stainless bolts, washers, and nuts with the nylon "locking" section. You can see the clamp in these photos. (my rear derailleur cable just clears the clamp vinyl)

Once i temporarily screwed on the "V" stainless fender support arms into the clamp, and layed the rear fender up inside the frame, i could see where i had to bend the rearward arm to pick up the back fender attachment point. I also saw that i would be cutting down the fender's overall length, as the inner bike facing side was hitting the ground.

Once my attachments points were set, and the fender cut off to ject below the bottom bracket area, i appached the fender to the support arms to get a measurement for the zip-tie frame attachment points that REALLY lock the rear fender in SOLID!

Here's the upper zip ties in place, where the tie wraps around the frame and connects through 2 elongated holes i fitted to each side of the fender. I used a white magic marker to mark the elongated hole positions, and cut them with a flex shaft machine and round ball bit worked to make a wider hole. A drill bit could be used also i suppose.....

.......ignore the road dust,.....i just got back from a short 6 mile commute to grab a bite to eat.

A similar set of elongated holes were cut into the lower bottom bracket area, as seen here:

.....and a view from inside the fender:

The overall profile:

Note: I decided to have the front fender attach to just before the fork crown, in order to make use of the taller 38x700c tire. Because this Surly LHT fork was not suspension corrected and made for 26" wheels, this tire would not allow for a fender to go under. A 28x700c tire would allow a more usual front fender setup, but i needed the extra "rise" to get my 170mm crank arms and pedals up a bit more. I do have a Surly LHT 700c frork coming later today that should "correct" for the lack of a 26" suspension fork, but that experimentation will come later.

I ended up altering the fork crown fender attachment mounting plate so as to allow the fender to rise up as high as possible,....basically flush with the fork crown. Here's the change i made to the fender mount:

Bending the metal to just clear my heaset:

From inside,...the fender now is flush with the inside of the fork crown> The "cork" was fitted to keep the road grit out!

Anyway,.....the rear fender is ROCK solid now, and in this all weather commuter setup i love the disc brakes and comfort of this setup.

Oh,....i ended up using some nice 3-M company Zip-Ties i located at a used tool store locally. (i bought several packs of 6 pieces each in 6" and 12" lengths, for $1 a pack) These are heavy duty and well made!

I've given up on the CHEAT Chinese made crap from my local automotive stores. They BREAK with such regularity i just threw out a bunch. Just seem way too brittle and not worth the aggravation.

MisterK 03-07-13 09:27 PM

ridgid 69er eh :lol:

joejeweler 03-09-13 07:18 PM


Originally Posted by MisterK (Post 15358876)
ridgid 69er eh :lol:

Nope,.....i believe i said it's a "rigid" 69er. :-)

......basically just a 69er but with a little more firmness out front. On my hardtail frame i need the extra rise to get my bottom bracket up! :D

.....and now i'm hearing the words and music of the chorus to an old classic tune......"Carolina in the Morning".....

"Nothing could be finer than to ride a 69er in the morning,......"

PatrickGSR94 03-11-13 02:57 PM

What's the purpose of running a 700c front wheel and 26" rear wheel?

joejeweler 03-11-13 09:17 PM


Originally Posted by PatrickGSR94 (Post 15373447)
What's the purpose of running a 700c front wheel and 26" rear wheel?

Sometimes a bike using a 700c (aka: wider rim "29er") front wheel matched with a 26" inch rear wheel is designed that way. The larger front wheel's ability to roll over objects with less effort, and a 26" wheel's natural ability to pick up speed quicker,......combine to make an interesting mix.

In my case,......i chose to go this route in order to get the geometry of the frame closer to the original designed specs. This frame originally came with an 80mm to 100mm suspension fork, with a much higher axle to fork crown length than the rigid 26" fork i am using. I bought just the bare frame, and wanted to run it rigid.

By fitting a 29er (700c) size wheel with as wide and deep a tire as i could (a Michelin City Protec 38x700c), and not going too fat on the rear (1.50x26 Serfas Drifter),....i was able to adjust the head tube angle closer to what the frame was designed for. This also brought the bottom bracket height up enough to avoid scraping the pedals as readily. This tire mix is actually pretty well matched, both in width and profile height.

Once completed, i found the bike handled quite well on the street, with no strange handling noted. But i didn't like the very little clearance of the front tire to the fork crown (maybe 2mm?). If i was going to run this strickly with the Surly LHT 26" fork,....i was going to downsize the tire height to a thinner 32x700c Serfas Drifter.

However, i've since aquired another Surley Long Haul Trucker fork in the taller 700c size, which brings the front end up another inch or so,......and adds a little more to my pedal clearance. With this fork there is plenty of tire clearance to add a normally fitted fender AND maintain the fatter/taller/more comfortable 38x700c tire.

All in all a very workable road solution to using a non suspension corrected fork in place of the designed for suspension fork.

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