I ride still an 2004 alu bike and 2004 disc wheel. (its still as good as I need my gear to be and do I really lose time … as my bike is as aero as an p2 they tell me ;- )
Recently I adviced an female client to try a disc wheel,she would not know much about gear as she focuses on training .
Anyway I got an txt after the first ride and she told me while she loved using a disc (non spoked ) she did find it harder to deal with the road bumps and overall found it a harsher ride .
I must say I was mildly suprised by this statement as Iam 99% sure that was an completely unbiased statement. and she is pretty oblivious if a handlebar is 6mm (note not cm;-) higher or lower , yet she felt the harsher ride.
Now that would go pretty well with the philosophy of some coaches that you run slower off the bike when you use a (non spoked disc. (more in the case of IM ) Something I do think too but I cant see the evidence.
So people who have used spoked disc wheels and non spoeked disc wheels how much (if ) do you notice the difference?
(or wheels whith disc covers for that matter which I consider a perfect alternative for all unsponsored athletes)
do you feel you run better of the bike with spoked wheels ?
and since i am at it do you think you run better off a full carbon bike vs alu frame , carbon seatpost, full carbon tri bar
(again i cant see reall evidence from hawaii results changing much since carbon )
is there any good science papers on it somebody could recommend?
There is no difference in running with any kind of wheel. If you spend the whole bike leg of a triathlon getting beat up by a harsh disc wheel, your sore ass may slow you down just a hair. Otherwise it’s all the same.
Same for carbon or alu bike. Frame material makes absolutely no difference in running ability.
“True” discs (i.e. no spokes) are noticeably harsher. I swapped out my covered spoked wheel for a rear trispoke (rigid as a disc, and compression vs. tension based) on some training rides and the increased jolt over bumps was notable. That being said, I don’t notice any difference in my runs (even for 70.3s), when I went from a covered wheel (CH areo cover) to my Renn disc.
I don’t run, so I can’t comment on that. But I have a lot of experience with Zipp discs, Renn discs and Hed Jet disc (spoked). We have a half IM nearby where much of the bike course is very rough tar and gravel. It beats the daylights out of you. I’ve had significantly better times the years I’ve used the HED Jet disc. It absorbs a lot more of the harshness.
Last year when I did a relay on this course, I was up against a guy on another team who was a Cat. 2. (I’m 54 years old and a cat … what, 6?) He should have kicked my ass all over the course. But he had a tubular Zipp disc and was convinced he’d be faster pumping that baby up to 180 psi. I was with him before the start when he was pumping it up and I told him he was crazy. I ran my Jet disc (C2) at about 85 psi. I beat him by 20 minutes! The rough sections didn’t bother me. He said they almost killed him. I’ve made that mistake on that course in the past. I know how bad it hurts and I can’t imagine that it wouldn’t dramatically impact your ability to run.
I’d say it’s very course-dependent, but if there’s rough pavement for any significant percentage of the course, a spoked wheel will be good and go easy on the tire pressure. Truthfully, being sensible about the tire pressure is probably more important than the spoked wheel thing, but there’s little argument that a spoked disc is more vertically compliant (while being stiffer, laterally, at the same time … which is a very good thing).
thanks for that reply too.
you make an interesting point with compresion and tension based pressure ( I cant judge the point as I dont have the expertise , could you expand on that, would be realy appreciated )
have you played around with air pressure to make the tri spoke less harsh?
There are no scientific studies out there that have attempted to correlate run splits with bike ride quality aspects(disc v non disc wheels, carbon frames vs alum frames, low pressure tire vs high pressure tire). It is well known that the solid disc wheels (zipp & renn) are much stiffer vertically in relation to spooked wheels and discs. Thus, if you keep the tires the same and the pressure the same, the solid disc will be harsh/rough.
Make sure your client is using larger volume tires, 23cc, and a pressure appropriate to her weight. If she is a small person she can probably get away with 90-100 psi on larger diameter tires. The larger tire volume and lower pressure should produce more compliance and give a smoother ride.
thanks for the reply
She is on 23 mm and was on 115 and since the race is on much better surface I think we will stick with 115 (she is tallish)
Personally, i do not find my disc harsher than my trainings wheel (but I ride very step and put a lot of weight on my shoulders)
Ps Again personally, I felt better running off the bike (also non spoke disc) with my softride (for IMs ) for olys I felt that the softride was costing me a bit time for the bike and produced the same run splits…
First to address the tire pressure issue. +/-5psi in your tires will outweigh any difference in harshness between wheels. Tire pressure should be calculated to minimize rolling resistance (CRR), not for comfort (after all it’s a race). One option with clincher versions of solid discs and trispokes is to use a tubeless tire (no spoke hole to cover), since these can be run at lower pressures without worrying about pinch flats.
Now for the reason spoked wheels are more comfortable. With wire spoked wheels, the hub is not supported by the spokes below it, it is actually hanging from the spokes above it (like a suspension bridge). In contrast, solid wheels and trispokes support the hub the same way a stone column supports a roof (i.e. the hub is resting on the carbon fiber below it for support). The result is that sold wheels have to be very rigid (like a stone column) to support the hub and are thus harsher over bumps. In contrast spoked wheels have the top spokes actually stretching a bit to absorb some of the shock (you can think of the spokes as very stiff springs).
