rensho3

For Natz this year, I upgraded to a FF 90 mm front wheel from a 60 mm wheel. I am sure glad I practiced with it to warm up at Rock Springs or my 500 would have been a disaster. It made me wobble a little on first set of turns but I still got silver.

carleton

Congrats!

Yeah, they take some getting used to.

Dalai

^^^This

https://www.uci.ch/mm/Document/News/R...-E_English.pdf

Article 1.3.018 In track competition, the use of a front disc wheel is only permitted in the specialities against the clock

https://www.uci.ch/mm/Document/News/R...NG_English.PDF

For the individual sprint, the front disc wheel is allowed for the qualifications (200m flying start) but not for the matches.

Dalai

I have double discs - definitely notice a difference in handling even indoors compared to a deep wheel such as the Hed Stinger 90 I used prior to buying the discs and still use as a front for road TT's.

MarkWW

Anybody have any input on the various 5 spoke wheels on the market right now? I've been focusing on the ffwd, pro, and mavic options, but it looks like navigator makes one that's decent.

carleton

The Navigator one is well-made and only slightly heavier than the iO. It's 1/6 the cost of the iO and comes in tubular or clincher, front or rear. Plus you can order it without decals. I think it's the best value by far.

Bulldogsprinter

I have the navigator one, so far all I can say it is good. National champs in Finland were won on them. (not by me, my mate flatted his IO and I lent him my navigator, he had nothing bad to say about them).

taras0000

Are the Navigator N5 directional? They look to me as if you could run them either way (no teardrop shape to the blades).

carleton

They are symmetrical.

gycho77

I'm trying to buy a look ergostem to get a good fit for my bike(planning to use Caleton's roller video for fitting)
I saw some Ergostem on the ebay, but I think it is overpriced.
So does anyone know a good website or a person to buy the stem?
Model does not matter.
Sorry for asking a stupid question.....

Baby Puke

Ok, this is weird and only tangentially related to track, but you guys are smart: Anybody know of a source for different length roller belts? I'm toying with the idea of setting my rollers up short enough for my son to ride. He's 4, so his bike is pretty tiny.

gtrob

I think there is a gyroscopic/momentum property to a disc wheel. Ive been on a front disc indoors as well and it feels like it wants to straight itself, definitely doesn't handle like even a 1080 does.

taras0000

Look into O-ring suppliers, O-ring drive belts. Here's one I found - DuraBelt Oring Belting, Oring Belts, Oring Drive Belt

I got a replacement belt (urethane) from a local supplier when I was living in Hamilton, Ontario. If there are any industrial O-ring suppliers near you, then maybe give them a ring and see if they'll sell you one over the counter if you come by to pick it up. That's how I got mine.

Baby Puke

Awesome, thanks! I found this one, too: O-Rings - Standard AS568, ISO 3601 | Apple Rubber Products O-rings up to 26" in diameter.
How who's the math genius that can help me figure out what size to buy? The bike's wheelbase is 62cm, my rollers have 3" drums. Ideas?

taras0000

It all depends on the spacing of the rear rollers, well, actually the distance from the front wheel roller to the front rear roller. What size wheels are on the bike? A 26" O-ring will give you a circumfrence of 81.7". Maths is basically going to be Belt length = (circumfrence of single roller diameter+(distance between axles X 2)). So 3" roller gives you a 9.42" circumfrence (probably less, because the diameter of the belt seat is usually smaller, maybe 8.5"). All that matters after that is the distance between the roller axles. Double that distance plus 8.5 will give you a fixed running length. You'll probably downsize from there to maintain tension. How much? Maybe measure the stock roller belt you have and figure out the fixed running length on your set up. Downsize using the same percentage difference I would say.

carleton

Diameter: 3" = 7.62cm

Circumference of 1 roller = diameter * Pi = 7.62Pi = 23.94cm

Length from center to center of front roller to first rear roller = Xcm
You know how the rear bike wheel sits behind the middle roller? I need to know the distance from the axle of the front roller to the axle of the middle roller.

Xcm = length of cord on topside of rollers.
11.97 = distance around front roller
Xcm = length of cord on bottom side of rollers
11.97 = distance around middle roller

2Xcm + 23.94cm = length of nylon cord*


Also, the cord should be slightly shorter than this being that it doesn't actually sit ON TOP of the roller, it's recessed a bit. So, the diameter is actually smaller than 3 inches. Let's say the slot is recessed 0.25", then the diameter the cord travels is actually 3 - 2*0.25 = 2.5 inches. Put 2.5 inches in the formula above and get a shorter cord.

Also, also. The cord should be sorta short and stretch so it's snug So, go even shorter...

EDIT: Dammit Taras. (It's like racing to be the first to finish a math test...and losing.)

carleton

Or...you could contact Kreitler and give them the diameter and the distance between the two rollers and ask them to make you one.

MarkWW

yeah, kreitler makes custom length belts. Dave perry ordered some for his roller racing setup. read here: Bike Works NYC Roller Racing Info

dunderhi

Thanks, I appreciate starting my day with a laugh!

Baby Puke

Thanks dudes! Math is not strong in me...

wens

McMaster is another source of various sizes of high strength polyurethane o-rings. The Parker o-ring handbook is available as a free pdf and has a pretty complete section on o-ring drive belts if you want to get really into the weeds.

taras0000

Such is life for Mathletes!

taras0000

That makes you a TryMathlete.

queerpunk

Do you do plyometrics?

What do you like to do?

Roadieonthetrac

Not really a question, but being a newbie, wanted to share my experiences on the track. Roadie for 7 years, which I started at age 53, had not been on a bike for 40 years prior. Did the Learn To Ride at the Burnaby Velodrome (22M) these past few weeks.Burnaby Velodrome Club | Track cycling at it's best!

I'm sure many of you know how awesome this sport is. Last night was my first Open Track and Novice Coached Rides. Rotating pace lines, fly down to sprint line fast pace lines and Flying 200.

For a guy like me, who was a distance runner, doing this was beyond amazing. First 200 not so great, having never done one before. I think my second one was under 15 seconds. I can see lots of improvements just by taking the right lines and accelerating at the right time prior to the start. I am absolutely loving this activity. It's also a huge and welcome change from only doing trainer or roller rides all winter. I do have some issues with the indoor track as I have problematic asthma. So, purchased a membership at the Velodrome and next week I purchase a track bike.