Component Questions...

[buldogge]

Hey Guys...I just grabbed a small '94 Kona Fire Mountain for my (tallish) 7yo to ride on rail trail/parks/etc. and need some opinions on component swaps.

The original Shimano Tourney cantis are junked. I see a lot of threads about Mini Vs for CX/dirt...but...what about "upgrading" old MTBs???

I can stay canti and get Avid Shortys or Tektro 720...or...go Mini V with Shimano Deore or Tektro 926???

Also, I would like to put shorter cranks on, and convert it to 1x7...Has anyone used the Origin 8 single speed cranks? (They can be had in 155mm and are only like $28 wholesale) Alternatively, any other opinions/leads on a short crankarm that will work for reasonable money??

TIA
-Mark in St. Louis

[oliver1850]

I would think regular Vs would be the way to go. I think I've got a set of Tektros.

Here's a short crank:

http://peoria.craigslist.org/bik/4046908028.html

[cmbicycles]

You will want to replace the brake levers if going from canti to V brakes. Canti brakes don't pull as much cable as the V brakes, so V's will not feel right w/o the correct levers.

[gdw]

Converting to v brakes might be more of a hassle than you anticipate. Check the frame's rear brake cable stops before doing anything. Some of the older Konas used a stop on the seat tube to guide the cable to the cantilever yoke. The "dog collar" was cantilever specific and not designed to hold the last section of housing that runs to the v brake arm.

[oliver1850]

Serotta made an add on cable stop for the rear brake cable, there are probably others out there. It's a split aluminum ring that clamps on the TT. If I was doing it, I'd probably make it to go over the seatpost, as you would only need to slit it on one side.

[buldogge]

Hey Guys...Thanx for the input.

Mark...Those cranks would be too short...I can put together the O8 ones for less $ as well.

gdw...The frame does use the ST collar...but.. I probably have or can modify something around here to work.

cmb...I thought that the lever issue lay with road levers, not MTB canti levers...???

Also, picked up an XT med cage RD today as well...

-Mark

[makmadoosel]

I did the same to a kona fire mountain years ago and I used one of these (http://www.rivbike.com/product-p/ca6.htm)

[oliver1850]

Mini-Vs work with road levers. If you're going to use a flat bar, might as well use full size V brakes.

[buldogge]

Should I just get Shimano 590/610 Deore Vs? They're actually cheaper than the Tektro 926s...???

-Mark

[buldogge]

I just added the single version of that to my order (O8/Taiwanese part)...

Thanx.

-Mark

I did the same to a kona fire mountain years ago and I used one of these (http://www.rivbike.com/product-p/ca6.htm)

[buldogge]

I think I'll just stick with the 926s (they're cheaper, my mistake) and get a pair of Tektro 316AG levers if I need them.

Also, he seemed fine with the 170s today...we did ~18 flat miles on the Katy...so...I'll leave the cranks alone. I can always machine down/tap a set of Truvativ or Bontrager from the shop if need be...

So, I guess I'm leaving the FD/triple in place. Can the Deore XT med cage I picked up handle the load? I'd like to lose the Tourney cranks for a Deore double instead, maybe...??? (and a Deore FD, I suppose)

-Mark

Mini-Vs work with road levers. If you're going to use a flat bar, might as well use full size V brakes.

[bargainguy]

Short cranks:

I've had Mark Stonich at www.bikesmithdesign.com shorten some relatively current cranks (9-sp 105 & Ultegra) for me to 148mm and 152mm. I believe he also sells short cranks outright as well. Not all cranks can be shortened, see the list.

Very reasonably priced. I think it was $50 plus return shipping if you removed the chainrings & bolts, and extra $7 if you didn't. Highly recommended, he does nice work.

[buldogge]

I'll have a look at the list...but...I can handle the machining myself (full machine shop capability).

TA
-Mark

Short cranks:

I've had Mark Stonich at www.bikesmithdesign.com shorten some relatively current cranks (9-sp 105 & Ultegra) for me to 148mm and 152mm. I believe he also sells short cranks outright as well. Not all cranks can be shortened, see the list.

Very reasonably priced. I think it was $50 plus return shipping if you removed the chainrings & bolts, and extra $7 if you didn't. Highly recommended, he does nice work.

[bargainguy]

You've got a full machine shop at your disposal? Excellent! I bet a lot of folks here would love to play in that kind of sandbox....assuming, of course, that they knew what they were doing....

[makmadoosel]

I need brake pads with the posts milled down just a bit, do you ever take on any really small jobs?

[buldogge]

Canti pad posts? Do you need them shortened, or the OD turned down??

-Mark

I need brake pads with the posts milled down just a bit, do you ever take on any really small jobs?

[oliver1850]

Lots of new Tektro V brake stuff here if you need it, and various FDs.

Older (8 speed - M737) GS cage XTs had 32 large cog capabilitly and 33 T capacity. That would be good for a 13-26 cassette and a 28/38/48 crank. With a 29/44 double you should be able to run an 11-28 cassette for sure, likely an 11-30 will be fine, maybe an 11-32.

[makmadoosel]

buldogge -

Both actually. They are for dia compe gc450 centerpull brakes. They took a special brake pad and the shoes available today don't fit the brake. I'd like to get some kool stops with replaceable shoes turned down to 6mm post diameter and made shorter. Exacerbating the issue, I am using 23mm rims and I don't have much pad room.

[buldogge]

Hey Mark...It's got an 11-28 7s cassette. I will probably change the crank to a double, eventually. Do you have an 7s XT FD?

Lots of new Tektro V brake stuff here if you need it, and various FDs.

Older (8 speed - M737) GS cage XTs had 32 large cog capabilitly and 33 T capacity. That would be good for a 13-26 cassette and a 28/38/48 crank. With a 29/44 double you should be able to run an 11-28 cassette for sure, likely an 11-30 will be fine, maybe an 11-32.

I could probably help you...my buddy is the actual machinist...let me ask him about holding the pad holder...

buldogge -

Both actually. They are for dia compe gc450 centerpull brakes. They took a special brake pad and the shoes available today don't fit the brake. I'd like to get some kool stops with replaceable shoes turned down to 6mm post diameter and made shorter. Exacerbating the issue, I am using 23mm rims and I don't have much pad room.

[cmbicycles]

Hey Guys...Thanx for the input.

cmb...I thought that the lever issue lay with road levers, not MTB canti levers...???


-Mark

I forget the actual numbers, but if you look at the length of the pivot arm on a canti lever vs. a V-brake lever, brake lever pivot bolt to cable mounting point, the V brake levers will be about 10-12mm longer as they need to pull a bit more cable to work right.

Road levers work with canti brakes, but not standard V brakes for the same reason, V brakes need more cable pull. Some mtn brake levers have an adjustment (avid speed dial and some tektro come to mind) where you can adjust that distance for V/Disc or Canti, it may be labeled as Hi-Lo, but that is why. It isn't that it won't work, it might, but not as well as it should.

[buldogge]

I ended up ordering the Mini-V 926s...so...I'm hoping I'll be gtg. If not, I'll grab some Tektro 316 levers.

-Mark

I forget the actual numbers, but if you look at the length of the pivot arm on a canti lever vs. a V-brake lever, brake lever pivot bolt to cable mounting point, the V brake levers will be about 10-12mm longer as they need to pull a bit more cable to work right.

Road levers work with canti brakes, but not standard V brakes for the same reason, V brakes need more cable pull. Some mtn brake levers have an adjustment (avid speed dial and some tektro come to mind) where you can adjust that distance for V/Disc or Canti, it may be labeled as Hi-Lo, but that is why. It isn't that it won't work, it might, but not as well as it should.