Mountain Bike Reviews Forum banner
1 - 20 of 55 Posts

·
Registered
Joined
·
186 Posts
Discussion Starter · #1 ·
I am designing my custom ti geared 29er right now.

I am trying to deside how long to make them.

What do you ride?

How long are your chainstays? (full suspension, softtail, hardtail)

How is the bike out of the saddle climbing? (are you spinning the rear tire?)
 

·
Recovering couch patato
Joined
·
14,019 Posts
For custom ti, perhaps doing some steel and alu test rides will give you the info you really need.

I say : go 445mm, and you'll be golden. Easy enough to get decent clearance, and well short enough to flick through tight singletrack. If you don't fall for the short chainstay lobby, up to 460mm should be fine also.
 

·
trail rat
Joined
·
7,825 Posts
Mine go all the way from the cranks to the rear wheels! Woo hoo! :eekster:

Steel, rigid - more traction than I can spin out the wheels util just before I have to walk.

Rear stays - 444mm from BB center to rear dropout in mid position of sliding dropouts that have 15mm movement in total.
 

·
Registered
Joined
·
804 Posts
440mm from the center of the EBB shell here; so, the effective chainstay can change, but, with the seat tube at 73 degrees, the wheel is always in the same position. I would add a good bit--maybe a centimeter or so--if I could do it again: the bike has a very tight feel, and I can loft the front wheel easily, but I'd trade some of this for stability. For the geeks out there, the frame has a 72 degree headtube angle, with a custom, 48mm rake fork. My next frame will have Paragon sliding dropouts, which should give me some options about chainstay length. I'm now of the opinion that short does not always eqaul best.
 

·
Registered
Joined
·
2,230 Posts
I think it's cool you're designing you own bike, however part of the custom deal is working with a guy who specializes in designing bikes (you'd hope), so details like that could perhaps be worked out with them.

We look at your position on the bike and adjust the CS length to suit, because in reality, CS length is just part of the contact points/weight distribution/wheelbase equation. It's not a figure you can just magically poll 6 random people on the internet and get an answer for.

Let your builder of choice work that out for you. That's what you're paying for.
 

·
www.badgercycles.com
Joined
·
309 Posts
Since it will be geared and if you want to clear all FD's with all the new tires coming out you will need no less than 450mm. Anything less and you will be smacking one of the new POS front DR's. Of course all this depends on your BB drop and ST angle.

That said I agree with Thylacine 100%.
 

·
Complete Bastard
Joined
·
2,282 Posts
Ahh designing your own bike. I would work with someone who has done this before, preferrably many times. While you may be able to design an acceptable bike by soliciting opinions on here, there are dynamics to this that you and I, as layman, have no idea about. It's good to have an expert weigh in on this.

As for what I ride - your mom. Chainstay length - long enough. Spinning the rear tire - hell yeah, I do burnouts in the parking lot with my chums and then we go smoke cigarettes behind the building.
 

·
try driving your car less
Joined
·
3,097 Posts
AteMrYeats said:
440mm from the center of the EBB shell here; so, the effective chainstay can change, but, with the seat tube at 73 degrees, the wheel is always in the same position. I would add a good bit--maybe a centimeter or so--if I could do it again: the bike has a very tight feel, and I can loft the front wheel easily, but I'd trade some of this for stability. For the geeks out there, the frame has a 72 degree headtube angle, with a custom, 48mm rake fork. My next frame will have Paragon sliding dropouts, which should give me some options about chainstay length. I'm now of the opinion that short does not always eqaul best.
do you think you could tell 1 cm difference in CS length? not bashing, but genuinely curious.
 

·
Registered
Joined
·
186 Posts
Discussion Starter · #12 ·
Thanks for all the responses.

Thylacine said:
I think it's cool you're designing you own bike, however part of the custom deal is working with a guy who specializes in designing bikes (you'd hope), so details like that could perhaps be worked out with them.
The problem is that I am the guy who specializes in designing bikes. I mainly do road bikes and work with Seven, Serotta, and Titus.

But now that I am making the "Big bucks" and I am a hard core mountain biker. I am going to get a custom ti bike for myself.

Thylacine said:
We look at your position on the bike and adjust the CS length to suit, because in reality, CS length is just part of the contact points/weight distribution/wheelbase equation. It's not a figure you can just magically poll 6 random people on the internet and get an answer for.
I am riding the Gary Fisher Paragon 2006 model right now. It has 44.5cm seat stays (Yes I know the catalog says they have 44cm but it is more like 44.5) I have owned a Kelly Roshambo, and a Surly K.M.

I was wondering what some of the other custom bikes are using for a chain stay length.

I have called Seven, Serotta, Titus, Orbea, and I.F. and talked to them about why they do what they do when they design there 29" bikes.

I am riding a friends 293 for the past couple days with a 46cm chain stay to see how the climbing performance is. (I know a full suspension bike is not the same as a hard tail.) I have really enjoyed that bike. I rode the new Caliber from Gary Fisher that felt better then the 293.

I am doing a random poll to see if anyone else brings up a point that I did not think off.

The main problem is the Ft. Der.

Thylacine said:
Let your builder of choice work that out for you. That's what you're paying for.
I believe I am going to get the Seven but am waiting to hear the final report.
 

·
Registered
Joined
·
804 Posts
jh_on_the_cape said:
do you think you could tell 1 cm difference in CS length? not bashing, but genuinely curious.
Good question. Maybe not, but that's one of the reasons I went with the Paragons. I could tell the difference between my custom and a Wily I was riding for a while: they had very similar geometry, though the Wily had slightly longer stays and a shorter top tube. The handling was drastically different, even with almost identical bar and saddle heights. I think a lot of it had to do with different bar set-ups, but I think the stays played a part. Could be wrong, though.
 

·
DiscoCowboy
Joined
·
342 Posts
Probably...

I 'thought' I could tell the difference with my Monkey when I switched the wheel from the back to front of the drops. Mostly climbing.

I spec'd my new ride out with 17.25" (438mm) and it rocks. Climbing, descending, sprinting, endurance racing, epic rides. Best handling bike I've ridden, it also has room for a 2.5 with mud clearance.

jh_on_the_cape said:
do you think you could tell 1 cm difference in CS length? not bashing, but genuinely curious.
 

·
highly visible
Joined
·
3,284 Posts
17.474" on my Vulture when the EBB is set for my usual 34x22 gear.

17.663" on my KM when I run it 40x18, 17.715" in 36x22.

I'm 5'7", 160 lb. 73 degree seat angle on both bikes. Saddle as far back as it will go with a conventional setback post on both bikes. Thudbuster on the Vulture shifts the saddle even further back when weighted. Of course seat angle and saddle position are relevant only while seated.

On the Vulture I run a Klaw, and traction is great. On the KM I run a Karma most of the time, and traction is fairly limited offroad. Obviously the difference has little to do with the extra 1/4" of chainstay length. I do think that for singlespeeders who stand out of the saddle a lot of the time it's good to keep the stays short, preferably 17.5". For geared riders, I suspect traction may actually be better with a slightly longer stay, since the weight ends up further back. Rider size may play a role in this too.
 

·
rigid bruce
Joined
·
179 Posts
At my current wheel position on my SS Curtlo it's 46cm. I could get it down to 44.5 if I wanted to. I don't think 1.5cm makes that much difference, but I prefer longer over shorter. I don't buy into the short chainstay idea for singlespeeds.

bruce boysen, loving my Curtlo in NW NJ.
 
1 - 20 of 55 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top