davidmikesell

I'm trying to install sks fenders on my friend's cannondale T800, and I've run into a problem. The rear fender is supposed to fasten to the brake bridge, through a 'horizontal' hole. Being the weird aluminum bike that it is, the cannondale has a type of 'wishbone' stay, and no brake bridge. The hole for fenders is 'horizontal,' on the underside of the wishbone stay. Here are some pictures



My plan is to measure a bunch, then drill through the fender, and install it with spacers. My questions are, has anyone done this? Is it okay to drill through sks fenders? Thanks!

J.C. Koto

Is the hole on the bike threaded? If so I'd be more inclined to buy or fabricate some kind of angle bracket and mount the fender to that.

I think most SKS fenders are aluminum sandwiched between layers of plastic so I don't know if drilling would cause delamination or if it'd be ok.

OldZephyr

Try a cable tie, or cable ties. A cable tie (or cable ties) could go around the seat stay above the "wishbone junction" and through the hole on the SKS fender mount (that is, the hole through which the brake bridge bolt ordinarily would have gone through). Not pretty, but most likely it would work. The "wishbone" would prevent the cable tie(s) from slipping down the seat stay.

urbanescapee

Yes, if they are the SKS Chromoplastic (aluminum sandwiched between plastic) they are very easy to drill thorough and shouldn't give you any trouble delaminating etc. I have drilled through them before to install fender mud flaps. SKS's own instructions read explicitly that you must drill in order to install their aftermarket fender flaps. However, for this application, I would either fold that tab flat or cut off the part that sticks out and leave the riveted part in place. Then drill a hole through the fender and the riveted plate so that it still has some good support in that area. If not, then remove the metal bracket altogether and sandwich the fender with some other metal sheet for support. That's how I'd do it.

But if you're like me, you've grown impatient and by the time you're reading this you've already done something about it that perhaps you wish you hadn't.

Wanderer

A piece of aluminum angle (L bracket) bolted to that U, will enable you to have the hole in the right place for mounting.

seeker333

I've done this on my Cannondale M500, which also has a monostay, but no fender mount (rivnut) as on the pictured T800. I drilled a hole, tapped it, then bolted straight through washer, fender and a rubber stopper as a spacer directly into monostay. It worked perfectly.

You can drill holes into SKS fenders, no problem at all, and you can cut them too, whether they're Al laminated or the cheaper all polycarbonate models.

Mount largest tire, then fit fender as carefully as possible, attaching at all points except monostay. When you've got it perfect, mark a spot on fender where you need to drill hole to provide monostay mount. You really need to completely bolt it into place to mark the hole location, otherwise you likely will get the hole location wrong, and end up with an ugly extra hole in your fender. After marking hole location, remove fender, drill hole, then refit fender.

Be sure to use a washer to help support plastic around hole (something more than just a bolt head). Use a round head bolt or similar that will not protrude into tire. You can make perfect fender washers from pennies and dimes, which is actually cheaper than real washers. Use rubber stopper, wine cork, presta valve nuts, etc for spacers between fender and monostay or chainstay bridge.

Doug64

Your plan will work just fine.

I just installed SKS fenders on this Cannondale T2 about a week ago. I have also installed them the same way on a Cannondale T800. The fenders on the T800 have been on the bike for 6 years and there have not been any problems.

Dry fit the fenders and carefully mark the hole where the fender will attach to the wishbone on the frame. use an awl or something sharp to "center punch" the hole location in the center of the fender. Drill.

As one of the posters, urbanescape, suggested, flaten the bracket supplied with the fender. You can locate it to the rear or the front of the fork on the fender. I put mine behind the fork. I think this bracket could be eliminated, and a large washer on each side of the fender would suffice. I might remove it on this bike if I take the fenders off for any reason.

A spacer will lower the fender, and reduce the gap between the fender and the tire. I am not sure what size tire I will be running on this bike, so I left the maximum gap. Those are 32 mm Conti Ultra Gatorskins on there now. They have a relatively low profile compared to some other tires.

Installation required patience and several dry fits to get the stays the correct length before cutting to fit.

We have 6 bikes in our family that have SKS fenders on them. They are tough and I have drilled multiple holes in some of them when switching them to a different bike or during fitting.







I picked up this pristine 2010 T2 a few weeks ago, and am thinking about trying it on a month-long tour starting next week. I only have about 300 miles on it and am a little ambivalent about taking it rather than my tried and true LHT.

skilsaw

I have the last of the T1's. The T2's have smaller chainrings... better gearing for loaded touring.
I never met a lower gear I didn't like.

Doug64

OT sorry

Yes, that is why I got this T2: the last year of the Cannnondale touring bikes, and the last of Cannondale's bikes made in the U.S. It is just like new, and it was also a heck of a good price.

We are starting in your neck of the woods, Vancouver, and riding to Montana via of Calgary. Low gears will be necessary for me. I already changed the crankset from a 48/36/26 to a 44/32/22, and think it work well on this bike.

When we return in August we will team up with our daughters and do a week long loop that will include Victoria.

davidmikesell

Thanks for all the help! I think I can do it now. I'll post pictures when I'm done.

trailmix

I know this is an older thread but if anybody has pictures of how they mounted fenders to a wishbone cannondale I would greatly appreciate it. My bike does not have the rivnut shown in the op's photo. Thanks

Doug64

What do you have to work with? Pictures?

seeker333

read #6

trailmix

I read your post but I was a little confused, it sounded like you drilled holes in the frame.

seeker333

You'll have to drill a hole too if you want to fix fender to Cdale monostay.

You can pop a rivnut into the hole, or skip it entirely like I described above.

fietsbob

As Pictured, above, the riv nut up in the crotch of the fork is what you use, it's already there ,
though a bit dirty because it is open to the wheel spray .. .

the 2 on the side of the monostay are for a rear rack . upper struts.

trailmix

As I mentioned before, my bike does not have the rivnut in the seat stay.
I guess I will fab a bracket that I can bolt to my rack to hold the fender.

fietsbob

Riv nuts are the common way to put a 5x0.8 mm"braze on " bottle boss mount into an aluminum frame,
my Koga Trekking bike has almost a dozen of them installed . factory job ..

most Shops would drill a hole and expand one to fit in it .

trailmix

I understand what a rivnut is and how it works. I am not interested in drilling holes in my frame.