Double wall rims from BMS - what tyres are compatible

[103Alex1]

Been looking at the rear eBike rims which BMS supply (26") and wondered if anyone who has ordered / used them can advise the range of tyres they will accommodate ? These are the ones which are supplied to build the wheel rather than the pre-built kits.

I know that the existing Bontrager front wheel rim that would stay on will run 26" x 1.5" - 2.2" (it has a 2.2 ACX on at the moment) and I'm looking at options for swapping the tyre on that. Ideally the new rear rim will take the same type of tyre as the front so anyone know the range of compatible tyre sizes I can look at ?

Thx.

 

[Jeremy]

I've used a couple of the 20" rims that BMS supply (although one actually came from GBK it was identical). They are remarkably good quality for the price, in my view. They are fairly narrow in section, but I've found that a 1.5" tyre fits perfectly well. One of my other bikes has very similar width rims and that has fairly fat MB style tyres (not sure of the size, but fatter than 1.5"). That doesn't seem to be a problem either.

I'd guess that they use exactly the same rim extrusion for all the rim sizes they sell.

 

[103Alex1]

That's helpful. Was wondering what the minimum width I could get away with was on the one hand. On the other, do you think they would take the 2.2 knobblys if I wanted to go off-road ?

Am I being ham-fisted with those presta valves trying to get them out of the rim when removing tyres or are they just very fragile and so prone to breaking when you are removing tight-fitting big tyres ? I've never had a schrader valve perish in 6 tyre changes.

 

[Deleted member 4366]

I have/had those rims on all my bikes. I usually use 1.95 for the road. I think they're 2.1s on my Rocky Mountain, and Saneagle has even bigger tyres on his Kraken, but not sure of the size.

 

[grldtnr]

Possibly ! I myself have managed to break the screw down valve a few times! Think t best to standardise all valve types for whole fleet of cycles , schader vales seem the bestt choice , but it is unlikely you could fit Schader valves to a sportive tyre.

That's helpful. Was wondering what the minimum width I could get away with was on the one hand. On the other, do you think they would take the 2.2 knobblys if I wanted to go off-road ?

Am I being ham-fisted with those presta valves trying to get them out of the rim when removing tyres or are they just very fragile and so prone to breaking when you are removing tight-fitting big tyres ? I've never had a schrader valve perish in 6 tyre changes.

 

[Jeremy]

I've just been out and checked, and the fat MTB tyres I have fitted to these rims are 2.125", so I can say for sure they are OK at this width.

You can easily drill a rim out to take Schrader valves rather than Presta, as long as you're not running narrow tyres. Personally I hate Presta valves with a passion, they just seem too fiddly. At least with Schrader valves I can use any pump around, including my compressor, rather than having to find where I put the one pump I have that fits Presta valves well.

 

[BAH48]

"Am I being ham-fisted with those presta valves"

You must be doing something wrong - I've never had a problem with them during 50 years of bike maintenance. Schrader valves are more convenient for me and I only buy tubes with them now.

 

[flecc]

Another vote for hating Presta valves, inconvenient, fiddly pumping procedure and easily broken. First thing I do on any bike supplied with them is drill out the rims and replace with Schrader valve tubes which can be pumped anywhere with almost any pump.

Presta valved tubes should be confined only to the skinny tyre road bike brigade, never used anywhere else.

 

[Old_Dave]

Not so much a hate... More of a good shunning, + another vote for the drill method


Sent from my iPhone using Tapatalk

 

[103Alex1]

Glad it's not just me with the presta thing ! When time comes to swap out the rear wheel I'll seriously think about drilling the front rim for schrader ones.

Main problem was getting the tyre off (and back on again) .. I suspect 2.125 was the max these rims were supposed to take so 2.2s were a real squeeze. Probably should have been more careful when removing the inner tubes but it was incredibly hard work getting the tyres off and back on (I don't use tyre levers to avoid damaging rims or tubes ... so I saved the rim and b*ggered the tube valve instead ) ... another drill method convert may soon be on the way !

I have learned some new skills over the last couple of days which has been great. Not done a final check for whether true yet, but have given both wheels a good service :

Front wheel and tyre off, broken spoke cut out, rubber lifted, broken bits removed and new nipple inserted, new spoke attached (spoke adjuster to the rescue !), brake disc off and cleaned with proper cleaner, bolts greased, new inner tube fitted, tyres replaced and pumped to proper pressure.

Rear wheel and tyre off, brake disc and spoke replacement as above, cassette removed (with help to unlock from LBS), spline and cassette thoroughly cleaned and replaced, locking nut threads greased for easy removal next time, new inner tube fitted and tyre replaced and pumped to correct pressure.

Wheelset's looking a lot better now - good enough to keep ...



and I'm bonding with the bike more and more each day... even if every kitchen surface is covered in bike tools and oily rags. Masses more to learn (wheel truing being next on the list), but at least I know a lot more about how wheels are set up than I did a couple of days ago. Can't get over how easy it is to work with a regular bike with lightweight components. Can't believe I never tried before.