Chainstay length question

[rw229]

How does chainstay length impact a frame's ride? I've always assumed that a longer chainstay would make for a more stable descending bike, but probably not climb as well.

I have a bike with a 72.75* ht, 73* st and 41.5 chainstays. I'm looking at a bike that has 72* ht, st and 45.5 seat stays. While the ht and st angles will slow things down, how will and additional 4cm of chainstay effect things?

[Ray]

You can't over-generalize - the idea is to get your weight distributed over the wheels (or the wheels situated under your weight) in a way that gets the proper weight distribution for good handling. That said, this can usually be done on a longer or shorter wheelbase bike, depending on use. That said, it sounds like you're currently riding a bike with racing geometry and you're looking at a bike with touring geometry - 45.5 cm stays are REALLY long and are usually designed that long to provide good heel clearance for panniers, if you're riding with them.

You can make bikes like that go as fast as a racing bike in a lot of circumstances, but it will not feel even remotely as responsive or lively. It will feel incredibly stable, but turn in on fast, twisty descents will feel really slow. Climbing out of the saddle will feel slower, applying power while honking along the flats will not give you that sensation of the bike jumping forward - everything will feel more deliberate. Of course, the front end steering geometry will have an impact on how this feels also, but with stays that long, the rear end is gonna feel PLANTED. Which can be a good thing or a bad thing, depending on what you're looking for.

-Ray

[eddief]

That is how I would describe it if I was an effective desciber.

[Peter P.]

With longer chainstays, you'll be getting the rear wheel a little further out from underneath you. I think that may reduce the effect of bumps a little bit.

It should have no effect on descending manners. To me, descending qualities are affected by handlebar height and front end geometry.

I have a bike with 44cm chainstays. While some will say the longer stays will flex more under power, I can't tell the difference.

[RPS]

I have a bike with a 72.75* ht, 73* st and 41.5 chainstays. I'm looking at a bike that has 72* ht, st and 45.5 seat stays.
Are the front center and wheelbase longer too? I'd look at all changes in combination, not just the chainstays.

[Marcusaurelius]

As someone stated chainstay length is just one of the things to look at. I think bottom bracket height is another one. I've never seen anything longer than 41.5cm chainstay on a road racing frame. I've only seen 44.5cm chainstay on a touring bike. The longer chainstay, relaxed head angle and fork rake makes a carrying heavy loads very easy. It's not the fastest thing on the road but it's very stable with loaded panniers.

For me personally I always look for a road racing bike with 73/73 angles 8cm bottom bracket drop and 41,5 chainstays.

[rw229]

Thanks for the detailed explanation.

You're correct in your assumption... I've been thinking about getting a more casual, all around Rivendell type bike. One of the options is the Atlantis which is where I came up with the chainstay question. Maybe I would be better suited by something a little sportier. I want relaxed, but don't want to have to "work" to get it to move when I want.


You can't over-generalize - the idea is to get your weight distributed over the wheels (or the wheels situated under your weight) in a way that gets the proper weight distribution for good handling. That said, this can usually be done on a longer or shorter wheelbase bike, depending on use. That said, it sounds like you're currently riding a bike with racing geometry and you're looking at a bike with touring geometry - 45.5 cm stays are REALLY long and are usually designed that long to provide good heel clearance for panniers, if you're riding with them.

You can make bikes like that go as fast as a racing bike in a lot of circumstances, but it will not feel even remotely as responsive or lively. It will feel incredibly stable, but turn in on fast, twisty descents will feel really slow. Climbing out of the saddle will feel slower, applying power while honking along the flats will not give you that sensation of the bike jumping forward - everything will feel more deliberate. Of course, the front end steering geometry will have an impact on how this feels also, but with stays that long, the rear end is gonna feel PLANTED. Which can be a good thing or a bad thing, depending on what you're looking for.

-Ray

[beungood]

Anyone ever ride the Great River Ride century in Westfield? I wanted to do a century this year as a goal and due to work have not yet tired one. I like the sound of this one even with the "Triple recomended" label but with the last 25 miles downhill i think it could be a good one to cut my teeth on. That and a Mount Greylock Hillclimb and I'd be happy this year...

[Ken Robb]

As a long-time motorcyclist not even my 63cm Riv Allrounder w/45cm chainstays seems "hard to move". It takes a bit harder nudge on the bars to initiate a turn than a race bike but nothing much more than the difference between pushing a Navy coffee mug across a table compared to a Limoges demitasse. OTOH it surely is reassuring to have the extra stability on fast descents and bumpy corners. It's nice that it's easy to ride straight when I'm really tired as well. All else being equal I guess a bigger/longer frame has to weigh a bit more since there is more of it so there would be some theoretical handicap on long climbs but since I weigh 200lbs nekkid a few ounces difference in bicycle weights in inconsequential for me.

[Johnnyg]

[QUOTE=beungood]Anyone ever ride the Great River Ride century in Westfield? I wanted to do a century this year as a goal and due to work have not yet tired one. I like the sound of this one even with the "Triple recomended" label but with the last 25 miles downhill i think it could be a good one to cut my teeth on. That and a Mount Greylock Hillclimb and I'd be happy this year...[/QUOTE Hi, I have done 13 of them and keep coming back for more, as in this year. It's certainly an epic ride. Lots of climbing, many good riders, food and music after. Just hope for decent weather. See you there. I'm riding a Storck. Their is life after a Serotta. Take care. JG

[bigreen505]

You can't over-generalize

I'll second that. I finally measured the chainstays on the bike that I thought was the best downhill and they are 39 cm. That floored me because my other bikes are 41 cm stays. I guess I always knew the back end of that bike was tight because getting the rear wheel in is a b*tch. That bike is also easy to change line mid corner but super stable. My other current bike has the aforementioned 41 cm stays, and has a weird combination of being simultaneously twitchy and feeling like a freight train -- the steering is twitchy, but trying to change lines takes planning and I have to push on the bike. On the bike with the longer stays I feel like I have to slide aft to get the bike to turn, where the shorter stay bike is much more neutral. The longer stay bike is all carbon with a stiffer fork and front end according to German magazine tests. Both forks have the same rake.

All this to say, measuring the bikes blew my assumption away and there clearly is a lot more going on then just chain stay length.

[Mark McM]

I've never seen anything longer than 41.5cm chainstay on a road racing frame. I've only seen 44.5cm chainstay on a touring bike. The longer chainstay, relaxed head angle and fork rake makes a carrying heavy loads very easy. It's not the fastest thing on the road but it's very stable with loaded panniers.

When talking about touring bikes, keep in mind that the primary reason for long chainstays is for foot/pedalling clearance when using panniers. If the bike also becomes more stable or has less shock transmission from wheel to saddle those are just fringe benefits.

[AndrewS]

Riv. makes the Rodeo, a "racing" bike with longish chainstays (43ish). The discussion about it's geometry on their site is worth a read - as long as you remember to bring the salt.

I have to wonder what you're getting at 45mm of chainstay. Longer can make more sense, but there is probably a point of vanishing returns.

Lynskey just started making a Ti road bike with relaxed geometry - the Sportive. 42.5mm chainstays, compared to the 40.8 on their standard road. The Gunnar Sport is similar, with 43mm stays. I think this sort of bike would be good for Randoneuring.

I'd be more inclined to look at these sort of sport bikes, rather than go to hugely long stays. I think you'll get that extra stability without hauling a lot of extra bike around.