Wheelbuilding / Wheel Building / Wheel build help

Anybody any experience with alexrim crostini 3.1 in 28h?

Lots of people on the weightweenies forum
https://www.google.com/search?hl=en&as_q=alex+crostini&as_sitesearch=weightweenies.starbike.com

It's worth bearing in mind that Alex made an offset R3.2 version for rear wheels which is about 50g heavier, suggesting that they intended the R3.1 as a front-only rim.

Ryde pulse sprint is 385g wide and quite stiff. Also available from U.K dealers.

At about 4x the price unfortunately...

I read last night that Jobst Brandt died last month.
Here seems most appropriate place on our forum to mention this.

His book, The Bicycle Wheel, is something anyone interested in wheel-building and the wheel as a structure should have a copy of.

He had very interesting ideas about many things including the benefits of slick tyres and the problems with Delta brakes.

His tour diaries are interesting too.

Since I found bits of writing by him it became clear to me that he was frustrated by the capitalist nature of bicycle design and manufacture, that is to say, changes for the sake of profit rather than for improvement.
I sympathise.

He tested components including rims and frames himself scientifically to determine what was best.

If more people like him were in charge of R&D the kit we have today would be even better.

Jobst Brandt 14/01/1935 - 05/05/2015

Here seems most appropriate place on our forum to mention this.

As true today as it was a month ago

:-)

Tx, saw that, but there's Google...

...then there's Tester, hence a Q here ;)

Hrm guys sells em as pair, both 3.1, that's no use then. Bike24 has rims, open pro are good but no doubt there's a cheaper alternative.

(Somewhere buried in this thread...)

Thanks for that - I've only just seen your reply - I've another question (if you don't mind)

Pumping the numbers in to the spoke calcs, I get

Sapim; F 291, R NDS 291, R DS 289
DT Swiss; F 290, R NDS 290, R DS 288

Whereas your spoke lengths are a bit shorter; F 289, R NDS 289 , R DS 288

Is that because the Laser spokes stretch more, being 1.5mm?

thanks

Steve

390 grams clinchers are bound to crack. The manufacturer will tell you that they are robust and all of that, but they will crack and then they will blame a faulty batch and this and that and that it is the one in a million... the reality is that an alloy clincher that weighs 390 grams is bound to crack and in my experience there is almost no exception to the rule, if you actually use the wheels

Tx ^{^

390g is prefectly adequate rim weight...

If it's a 32 or 36 hole 26" Mavic XC717Disc.

I was talking about rim braked 700 c rims.

I have yet to find a rim of that weight that doesn't need rim washers/low tension/high spoke count and a lot of luck to stay together.
In fact I have stories of rims just over 400 grams cracking, but I prefer not to go on a tangent and be cursed forever for that...

Sorry, should have hashtagged it:

#trollpost

Not perse...the weight weenie guy said those 430 alu rims in 28h crack at the rear..

Ah well, its for commuting and some potholes here have mineral rights...

My google fu is being a bit weak this morning.

Looking to pick up two novatec hubs (for different wheelbuilds)

http://www.cnc-bike.de/product_info.php?products_id=5920
which I think is a F172SB
http://novatecusa.net/project/f172sb-rh-f272sb-rh/

Which has the PCD, but not the center-flange measurements

and
http://www.cnc-bike.de/product_info.php?products_id=13295
which looks like it might be an older model of 751SB
http://novatecusa.net/project/751sb/

But totally stumped. Can't find any tech docs at all : /

ryde Pulse Sprint is 390g and seems not to crack so long tension are keep under 1200N and rider weight is not too high I think the limit is around 80kg. The old stans 340 rims where too light and did crack the newer version is better. The Kinlin XR-200 is one I have used a few time and again has not cracked to my knowledge (mine certainly have not) but again spoke tension and rider weight are the enemies of these rims.

for 390g rims keep tensions no higher than 1200N for DS 1150N is better and riders weight to less than 80kg but the lighter the better. this will keep problems to a minimum.

What do you want to know about the novatec hubs. A bit confused what you are asking.

I abandoned a wheel build today - a radial 20h front wheel ended up with spokes 4mm too long.

Measured everything twice again, spoke calculator said everything should be fine. Measured again, calculated again. Horror.

Ordered 4mm shorter spokes - still no explanation why the spokes doesn't fit in the real world. My head is dizzy.

So, to save 5 grams over a Mavic Open Pro it's another £25-£40 (depending where you get OP) more per rim for ryde Pulse Sprint if chickencycles price is right?

(assuming Mavic isn't full of it when they say weight is 435) :)

Is there some kind of reverse spoke calc tool, that given a rim, spoke length and pattern then returns all the hubs that would 'fit'?

I have a nice MTB rear where the freehub is dying, and getting a replacement might be difficult / impossible.

Now that's a damn good idea. I might then get round to using some of the bits of wheels I have.

Y U no new spokes?

(assuming Mavic isn't full of it when they say weight is 435)

That's a bold assumption, 450-460g is a more realistic range for current production, they haven't been 435g for the best part of a decade.

Ah, that then also explains why Open Pro are stronger: 20-30 grams more aluminium ;)

They are quite nice DT swiss spokes that haven't had a whole lot of use really.

If i have to replace the spokes, it pushes it in to beyond economic repair territory

In which case I'll buy some factory mavic UST wheels

Or just bin the lot and get a 29er

I'm expecting my mis-matched gold chris king hubs back this week.
I'm almost excited