Author Topic: Alternative rim to Mavic Open Pro (Read 6839 times)

jamesld8 · « **on:** 02 March, 2016, 03:58:20 pm »

Looks as if rear Open Pro will soon be due replacing, sidewalls are at 1.2mm in places. Built 32 spokes, 3x onto Hope Pro II.

I would like to reuse existing spokes, they`re fairly new replaced with last new rim. Rim has to be black, and I`d be using 25mm -28 mm tyres. Not racing , just riding / audax / rim brakes useage

Looking at Edd spoke calculator two alternatives seem close to mark; 1 Rigida Chrina but existing spokes are 1.4 mm too short OR 2 Exal LX17, spokes are 1.5 mm too long. Both are obviously heavier so sidewalls I`d hope would last longer. Not interested in XR2 as had 2 x wheels eyelets pull thro with these rims recently.

Any other suggestions, thoughts on best rim ?

thanks

LittleWheelsandBig · « **Reply #1 on:** 02 March, 2016, 04:05:49 pm »

Replacing rims at 1.2mm is overly conservative in my experience. Failure usually occurs below 1.0mm.

jamesld8 · « **Reply #2 on:** 02 March, 2016, 04:10:26 pm »

Quote from: LittleWheelsandBig on 02 March, 2016, 04:05:49 pm

Replacing rims at 1.2mm is overly conservative in my experience. Failure usually occurs below 1.0mm.

fair enough---maybe a couple thousand miles more in them but they`re still due replacing by summer this year I`d think

Torslanda · « **Reply #3 on:** 02 March, 2016, 04:44:23 pm »

Ambrosio Evolution for me. For any other alternative I'd suggest a chat with Mike Conway, it's what he does.

Somnolent · « **Reply #4 on:** 02 March, 2016, 09:37:58 pm »

Quote from: jamesld8 on 02 March, 2016, 03:58:20 pm

Rigida Chrina but existing spokes are 1.4 mm too short

It is possible to build with the existing spokes - but quite challenging. Threads only just engaged at lacing, any more than a turn or two at the most and you'll never do it.

Not a rim I'll ever use again - real bar steward to get tyres on and off (compared with the OP)

Quote from: jamesld8 on 02 March, 2016, 03:58:20 pm

OR 2 Exal LX17, spokes are 1.5 mm too long.

I'd be worried about bottoming out the threads... but again it's a rim with a reputation for being tough to mount/dismount tyres, so I'll not be trying it.

Choices are a bit limited at 605 ERD - why not another Open Pro?

Crumbling Nick · « **Reply #5 on:** 02 March, 2016, 10:22:24 pm »

Quote from: LittleWheelsandBig on 02 March, 2016, 04:05:49 pm

Replacing rims at 1.2mm is overly conservative in my experience. Failure usually occurs below 1.0mm.

+1
All my Open Pros have only measured 1.3mm when new. That's a lot thinner than 1.7mm typical of touring rims. If you use 1.0mm as a minimum thickness (that was also advised by Chris Juden, formerly CTC's Technical Officer), your rim is only 1/3 worn.

Ross K · « **Reply #6 on:** 03 March, 2016, 06:05:07 am »

I'm a long-time Open Pro fan but have recently moved to (identical weight) Ambrosio Excellight. I think they could use the same spokes but you'd have to check. Usually Planet X do them for £50.

Another option, which I used to replace a pair of Open Pros on a winter bike, is Open Sport. Some snobbery can be found online about their "inferior" stapled joint and slightly higher weight but the truth is I can't tell the difference* and I like the brake track wear indicator too.

* Not only can I not tell the difference, the joint is undetectable under braking, unlike my "better" Open Pro wheels.

Biggsy · « **Reply #7 on:** 03 March, 2016, 03:03:31 pm »

Open Pros can be used down to 0.7mm according to lots of users, although I'm not necessarily condoning that myself.

Trouble is, not many alternatives to Mavic rims, and Open Pros in particular, are as easy to fit tyres to.

Bledlow · « **Reply #8 on:** 03 March, 2016, 05:16:08 pm »

Quote from: Ross K on 03 March, 2016, 06:05:07 am

I'm a long-time Open Pro fan but have recently moved to (identical weight) Ambrosio Excellight. I think they could use the same spokes but you'd have to check. Usually Planet X do them for £50.

Another option, which I used to replace a pair of Open Pros on a winter bike, is Open Sport. Some snobbery can be found online about their "inferior" stapled joint and slightly higher weight but the truth is I can't tell the difference* and I like the brake track wear indicator too.

* Not only can I not tell the difference, the joint is undetectable under braking, unlike my "better" Open Pro wheels.

Mrs B has had an Open Sport back wheel for just over a year & is very happy - as in she has nothing to say about it. It does the job without her noticing anything except that it goes round.

jamesld8 · « **Reply #9 on:** 03 March, 2016, 05:42:49 pm »

Quote from: Biggsy on 03 March, 2016, 03:03:31 pm

Trouble is, not many alternatives to Mavic rims, and Open Pros in particular, are as easy to fit tyres to.

wise words indeed, as an owner of a front XR2 dynamo wheel I dread having to remove and refit any tyre to it

on RD 300 last year I had to replace front as it had got casing damage, needed to ask nice friendly bike shop mechanic to fit the new (Conti Gsport 25mm) one as I just could not get it on

mattc · « **Reply #10 on:** 03 March, 2016, 07:33:41 pm »

Quote from: Ross K on 03 March, 2016, 06:05:07 am

Another option, which I used to replace a pair of Open Pros on a winter bike, is Open Sport. Some snobbery can be found online about their "inferior" stapled joint and slightly higher weight but the truth is I can't tell the difference* and I like the brake track wear indicator too.

* Not only can I not tell the difference, the joint is undetectable under braking, unlike my "better" Open Pro wheels.

I thought the Open Sport took a slightly different length spoke?
(havent checked the calculator thingies)

mzjo · « **Reply #11 on:** 03 March, 2016, 08:59:26 pm »

I was going to suggest Open Sport but I am fairly certain that they are shallower than Open Pro (certainly mine seem to be shallower than the old Open Sup). I also like the CXP22 rims which build up very nicely but they are probably deeper than Open Pros (although not visibly by very much). Snobs will say that they are too cheap but anything new is expensive to me.

Ross K · « **Reply #12 on:** 03 March, 2016, 09:14:29 pm »

Sorry, I misled you folks, there is indeed a difference in ERD Pro vs Sport so they cannot be swapped - my recent wheels with Sport rims was a actually a new build, with new hubs, not just a rim replacement (although they did replace a pair of Open Pro wheels).

Either my memory is failing me or I have too many pairs of wheels!

halvis · « **Reply #13 on:** 04 March, 2016, 10:02:54 pm »

H Plus Son Archetype rims work really well with 25mm tyres IMO.

Compared to my Open Pro build they were certainly stiffer, but more comfortable down to the wider rim.

Slightly heavier, but not enough to worry about.

Somnolent · « **Reply #14 on:** 20 June, 2020, 10:04:48 pm »

Quote from: Somnolent on 02 March, 2016, 09:37:58 pm

Quote from: jamesld8 on 02 March, 2016, 03:58:20 pm
Rigida Chrina but existing spokes are 1.4 mm too short
It is possible to build with the existing spokes - but quite challenging. Threads only just engaged at lacing, any more than a turn or two at the most and you'll never do it.

Not a rim I'll ever use again - real bar steward to get tyres on and off (compared with the OP)

Quote from: jamesld8 on 02 March, 2016, 03:58:20 pm
OR 2 Exal LX17, spokes are 1.5 mm too long.
I'd be worried about bottoming out the threads... but again it's a rim with a reputation for being tough to mount/dismount tyres, so I'll not be trying it.

Choices are a bit limited at 605 ERD - why not another Open Pro?

To answer my own question ....
Here's why not

Fixed a puncture roadside, inflates to a get-me-home 60psi. Topped when home to 90 psi
Next morning it's flat again... bugger it must be thorn in the tyre that I missed.... nope it's

despite still having 1.5 mm rim thickness adjacent to the spilt.

Archetypes are bit expensive for the commuter - any other suggestions currently?

LittleWheelsandBig · « **Reply #15 on:** 20 June, 2020, 10:20:25 pm »

That is unlucky. There must be a lot of variation in residual wall thickness from the machining.

Kinlin ADHN are heavier and wider than an Open Pro but they also have a 605 ERD. The current fashion for wider rims with skinny tyres might make these rims on trend. Swapping tyres is not too tough.

Brucey · « **Reply #16 on:** 20 June, 2020, 10:59:05 pm »

IME brand new open pro (now open pro C) rims are only 1.35mm thickness if you are lucky. I don't believe that a failed rim was 1.5mm thickness, not for a moment. Replacing rims that are 1.2mm is being excessively conservative IMHO, if the measurements are accurate.

If you are determined to re-use the old spokes then sometimes you can, if you increase the number of spoke crossings by one and use a smaller ERD rim too. It varies with the drilling/crossing and hub you are using of course

For example

32x3 SF with 605mm ERD = 32x4 SF with ~590mm ERD
36x3 SF with 605mm ERD = 36x4 SF with ~592mm ERD
36x3 LF with 605mm ERD = 36x4 LF with ~583mm ERD
32x3 LF with 605mm ERD = 32x4 LF with ~580mm ERD

If you change to a larger ERD rim you can similarly reduce the number of crossings (which tends to make slightly less difference if you start with x3.

The other option is to cut the old spokes down and rethread them to suit rims with a slightly smaller ERD.

cheers

Somnolent · « **Reply #17 on:** 21 June, 2020, 11:12:24 am »

Quote from: Brucey on 20 June, 2020, 10:59:05 pm

I don't believe that a failed rim was 1.5mm thickness, not for a moment. Replacing rims that are 1.2mm is being excessively conservative IMHO, if the measurements are accurate.

On careful re-measurement the rim picture above comes out at 1 mm (note to self: don't try using a jeweler's deuxieme gauge in a hurry and in poor light!)

However the experience meant that I started checking a lot more wheels in the family's stable of bikes.
Another Open Pro I won't be riding again - and this one does measure 1.2mm under the hook where you can get the gauge in.
Looks to me as if the "rippling" (that you'd expect to be at the thinnest point) is actually in the box section, where of course there is no way of measuring the thickness until I cut through it.

Somnolent · « **Reply #18 on:** 21 June, 2020, 11:13:20 am »

Quote from: LittleWheelsandBig on 20 June, 2020, 10:20:25 pm

Kinlin ADHN are heavier and wider than an Open Pro but they also have a 605 ERD. The current fashion for wider rims with skinny tyres might make these rims on trend. Swapping tyres is not too tough.

Thanks - two on order!

Brucey · « **Reply #19 on:** 21 June, 2020, 11:26:13 am »

Quote from: LittleWheelsandBig on 20 June, 2020, 10:20:25 pm

That is unlucky. There must be a lot of variation in residual wall thickness from the machining.

yep. The whole argument for machined braking surfaces was that it allowed some freedom from the manufacturing tolerances of the extrusion.

However...ironically enough the quality of the extrusion still dominates the rim quality, just in a slightly different way: I've measured quite a few modern rims and they are mostly crap, with significant side-to-side variations in rim wall thickness, rim-to-rim variations in wall thickness, and of course variations in thickness within one side of a rim, simply because the extrusion wasn't anywhere near straight before they started to machine it.

Obviously the life of the rim is limited by the thinnest part.

Come back unmachined rims, all is forgiven....

cheers

vorsprung · « **Reply #20 on:** 21 June, 2020, 05:50:21 pm »

I did a straight transfer/rim replacement of Open Pros to LX17 a couple of years ago

They've been fine, that's what I rode the last PBP on

My rear hub is also a Hope Pro II

Somnolent · « **Reply #21 on:** 28 June, 2020, 04:28:13 pm »

The rim with the "ripple" in it when sectioned:

down to about 0.5mm thickness in the box section where the ripple was.
After cutting through at that point it was easy to twist the rim to destruction at another point:

There, I measured 0.3mm adjacent to the "crack" although there could have been some thinning due to elongation in my "abuse"

I then sectioned the rim which had failed under the hook (not in the box section at all.

Although the thickness was 1mm at the point of the split, there were sections in the box which were down to 0.7mm.

Some of this may be down to cheap and fairly abrasive pads set up not quite parallel to the rims, but as LWaB said earlier:

Quote

There must be a lot of variation in residual wall thickness from the machining.

Personally I certainly shan't be buying Open Pros again, and will be treating at any lightweight rim with machined brake track with a lot more caution in the future.

rogerzilla · « **Reply #22 on:** 28 June, 2020, 05:17:45 pm »

Machined braking surfaces came about to solve a problem that needn't have existed, i.e. hard anodised braking surfaces. These are a Bit Crap in the wet until they eventually get ground back to metal*, so rim manufacturers started machining off the anodising. Silver anodised rims have much shallower anodising and don't need machining (it wears off after a couple of wet rides) but hey, added value and marketing.

So you now pay for black rims that are more prone to cracking AND to have the black machined off after it's been put on.

*can take a whole winter of wet riding, and they don't look great while it's happening because the wear rate differs depending on proximity to a spoke eyelet: https://www.ebay.com/itm/USED-Mavic-Open-4-cd-32H-700c-nipples-stuck-presta-CLINCHER/274353521438?pageci=b378861c-a15e-417f-ba44-0fe14f185d2d

Brucey · « **Reply #23 on:** 29 June, 2020, 08:11:17 am »

Quote from: rogerzilla on 28 June, 2020, 05:17:45 pm

Machined braking surfaces came about to solve a problem that needn't have existed, i.e. hard anodised braking surfaces....

If that were the case then you would presumably only find machining on anodised rims.

cheers

alexb · « **Reply #24 on:** 29 June, 2020, 09:22:28 pm »

I did a straight swap from Open Pros to Open Sports (taped the new rim to the old and moved the spokes across). It worked fine. I really like the Open Sports. I batter my rims by riding the bike off road a lot and they are holding up really well. Cheap as chips too. For their replacement, is be tempted to go even cheaper with the A119 which is a bit wider and takes slightly fatter tyres. As for breaking, I've found Shimano Dura ace/Ultegra brake blocks area really good balance between performance and rim wear.