Completely ignoring the issue of vertical or rear-facing dropouts, in general, would a triathlon bike frame (with tri geometry) converted to run track drop handlebars make a very good track bike? Lots of people seem to say that tri bikes don’t have the quick handling of road bikes, and very quick handling is essential in many track events. So would this work? Would it work well?
One of the biggest issues would be bottom bracket height. A track bike has a higher bottom bracket so the pedal will not hit the steep banking of the track. I wouldn’t recommend it.
Any idea of what’s needed or typical for track bikes’ BB height?
+1 Bottom Bracket height will be your biggest issue. Some velodromes specify a minimum BB height – 27-28cm, based on some quick Google searches, measured to the center of the spindle. Beyond that, I would think the usual Tri/TT geometry would be more suited to pursuit bars than drop handlebars.
eta: My Tiemeyer is 28cm and I run 165mm cranks. If you are determined to run longer cranks, you might want to bump up the BB some more.
Don’t older Cervelos have fairly high BBs?
How about the handling? Will a tri bike handle well on the track?
Depends on the rider, but generally no
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Depends on the rider, but generally no
Even this one will handle poorly?
(size-for-size, identical geometry to the cervelo P4 tri frame)
Oddly enough, that might work. Like triathletes, track sprinters like to be far forward on the saddle. In sprint events up to the Kilo and Keirin the UCI does not enforce the 5cm setback rule - you can have the tip of the saddle right up to the crank spindle. So, the more upright seat tube on a Tri bike would actually be what you want.
The other big question would be how much trail is there on the front fork (how far behind the front axle is the steering line of the head tube). The less trail, the more nimble (or twitchy) the handling. On my Tiemeyer it is 40mm (which was built to be a ‘jack of all trades’ and not a dedicated sprint bike). On my Guru Tri/TT bike, it is 43mm. If you go to Tiemeyer’s website and look at the drawings for his off-the-shelf frames, he uses 33mm of trail:
http://www.tiemeyercycles.com/track.html
So I would imagine most Tri/TT bikes would be more stable (or sluggish, depending on your point of view) on the velodrome, although the saddle position could actually be pretty good.
According to the cervelo website, whatever the fork trail is (it is not specified), based on other geometry dimensions, the trail is the same on their T4 track bike as it is(was) on the P4 road bike.
That may be – in my (very limited) experience with velodrome racing, I haven’t seen many Cervelos used by sprinters. OTOH, when I was at Masters Track Nationals in C-Springs back in July, I seem to recall the guy who won both Points and Scratch races for age group 55-59 was riding a Cervelo, a T3 I think. Points and Scratch are longer events, so more stable/less nimble would work.
Don’t older Cervelos have fairly high BBs?
Yes.
Dr Coggan’s wife used a P2 on the track, I think.
Edit - found the thread:
http://forum.slowtwitch.com/gforum.cgi?post=1551337;search_string=cervelo%20p2%20track;#1551337
http://forum.slowtwitch.com/gforum.cgi?post=737958;search_string=P3%20track;#737958
I’d say yes but it depends on what you are using it for. A tri bike is meant to go straight , a track bike is meant to have quicker handling. So for pursuit and the kilometer (basically TT events) it should work fine. For match sprint, points miss and out etc its proably not optimal.
Aside from that the high B is odd for a road frame but works well for a track frame so thats one of the few frames that would even be allowed on some tracks, and I suspect that if Cervelo was making a clean sheet frame they would’ve tweaked the geometry rather than just used the same molds, but thats a very expensive tweak for a low volume seller.
Keep in mind poorly is kind of harsh, really it should be not optimal
Is that an issue if you ride it around town wearing skinny jeans and drinking PBR?
Specialized Transition on the Track
Yes you can, but it probably depends on a lot of things. The photo I’ve linked was taken at the Hellyer Velodrome in San Jose which is a very flat 336 meter track. Something like 22 degrees in the corners compared to 28 at T-Town, 33 at Alkek in Houston and 45 at most 250m tracks.
I had 175mm cranks on there, but am not sure if I could have gotten away with that at say Frisco or ADT in Carson. My team mate did win a bunch of world masters titles on a Transition at the Dunc Gray velodrome in Sydney. Even still it I think for the most part it’s not optimal.
In my case, I sold my track bike some years before and when they decided to hold track nationals at my local track I just used what I had available. In Larry’s case, he was traveling to Sydney and also going for a world record in the pursuit (which he got) and didn’t want to bother bringing his normal track bike also.
Rear wheels are tricky. I borrowed a Campy track disk and had to buy a longer axle and a few more spacers to make the rear wheel match the width of my Transition. Another team mate (and former professional world pursuit champion Mike McCarthy) used his road P3 and just squeezed the rear dropouts together to make it work. We all cringed as we watched the rear drop out squeeze together as he tightened down the nuts on his rear wheel. Larry used the Zipp track axle and just added a 2mm spacer on either side to make it work.
Having done it though, it is a royal pain in the ass to strip down a TT bike and then put it back together for road action again. Especially if it’s got special brakes like the Transition does.
Track frames are really cheap…
Good luck.
Yes you can, but it probably depends on a lot of things. The photo I’ve linked was taken at the Hellyer Velodrome in San Jose which is a very flat 336 meter track. Something like 22 degrees in the corners compared to 28 at T-Town, 33 at Alkek in Houston and 45 at most 250m tracks.
I was at Rock Hill, SC (42 degrees) a few weeks ago, and a guy riding a Leader track bike with 172.5 cranks hit a pedal and almost went down. But someone said that frame is known for having a BB lower than a normal track frame. They then made him ride one of the rental bikes. (which was a Pinarello!)
At our new track in Cleveland, at 166m and 50 degree banking, I don’t think you could get away with a road frame unless you were pretty careful (this is all coming from a track novice, mind you)
That brings back painful memories - you got 20 points when you caught up to me which says where I was in the pack.
Agree on just buying a track frame and be done with it. You get a 120mm rear end to use standard wheels and the ability to change gears with out changing the chain. Road geometry works fine on bigger tracks, there is an early morning tri bike parade around Marymoor. Pursuit and mass start on steeper tracks if you survive the warmup laps.
You can find very nice used track frame for 500-1000 and another bike is always a good idea.
Having done it though, it is a royal pain in the ass to strip down a TT bike and then put it back together for road action again. Especially if it’s got special brakes like the Transition does.
Track frames are really cheap…
A couple years ago I looked into this with my Cervelo TT frame and even with an experience track mechanic, he said it would be expensive and a pain. Go with another track frame. Which I will WHEN we get a freaking track.
trackless clm
I think that I lot of tt/tri bikes have pretty high BBs - 45-60mm drop. With short cranks (say 165), you should be fine on a lot of tracks with that amount of drop. If you’re on the edge, make sure you use wider tires (25s) to give a bit of extra clearance. Also, the pedals you use would matter also.
Finally, if you are going fast, then the whole thing matters less. The only time you’re vertical on the banking is when you’re going very slow. Keep the pace higher and you’ll be more concerned about 2.5Gs pushing you down in the banking than BB drop…