30mm wide rims on Tarmac SL6
#1
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30mm wide rims on Tarmac SL6
Hi folks.
Following on my fom my new wheels threads, my bike mechanic buddy can get me a great deal on some Bontragers (RSL 51): However, they are 23mm internal, 30mm external width. Specialized say my SL6 can take up to 30mm tires, so it should be fine, but does anyone have any real world experience?
I understand Bontrager tested them with 25mm R3 tires and I believe they blow up to 29.5mm so, again, they should be OK, but I want to be sure.
Thanks for your help.
Following on my fom my new wheels threads, my bike mechanic buddy can get me a great deal on some Bontragers (RSL 51): However, they are 23mm internal, 30mm external width. Specialized say my SL6 can take up to 30mm tires, so it should be fine, but does anyone have any real world experience?
I understand Bontrager tested them with 25mm R3 tires and I believe they blow up to 29.5mm so, again, they should be OK, but I want to be sure.
Thanks for your help.
#2
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Why can't you measure your frame?
Typically, when a manufacturer says that their frame fits XX tires, it means that there's XX + 4mm on each side (generally considered the minimum debris/wheel deflection clearance), so if Specialized says that it'll fit 30mm, there should be at least 38mm between the stays/forks.
You could also look at your current wheels/tires and use hex keys as feeler gauges at the pinch points - if, for instance, you know that your rims are 24mm wide, you should be able to slide in a 6mm hex on either side, with a mm or so of wiggle room, you're at 38mm (~7mm+24mm+~7mm).
Like most manufacturers, Specialized/Roval are going wide with their wheels - I wouldn't be surprised if the 30mm figure is a little conservative and slightly larger could fit, while providing appropriate clearance.
Typically, when a manufacturer says that their frame fits XX tires, it means that there's XX + 4mm on each side (generally considered the minimum debris/wheel deflection clearance), so if Specialized says that it'll fit 30mm, there should be at least 38mm between the stays/forks.
You could also look at your current wheels/tires and use hex keys as feeler gauges at the pinch points - if, for instance, you know that your rims are 24mm wide, you should be able to slide in a 6mm hex on either side, with a mm or so of wiggle room, you're at 38mm (~7mm+24mm+~7mm).
Like most manufacturers, Specialized/Roval are going wide with their wheels - I wouldn't be surprised if the 30mm figure is a little conservative and slightly larger could fit, while providing appropriate clearance.
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The area where the tire is widest is well about the rim. I bet you would be fine with tires that measure 32. The rims are of no concern.
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I want to know this mechanic buddy
I have a set of Pro 51 on a 2019 SL6. Set up with 25mm GP5000 (which measure ~28mm on these wheels), they fit fine. The 25s look a bit narrow, but wider tires could be a close fit with the frame (and probably would be less aero for these wheels).
I have a set of Pro 51 on a 2019 SL6. Set up with 25mm GP5000 (which measure ~28mm on these wheels), they fit fine. The 25s look a bit narrow, but wider tires could be a close fit with the frame (and probably would be less aero for these wheels).
Last edited by nebula; 08-08-23 at 01:53 PM.
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#5
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Apparently, Bontrager do their aero testing of these rims with Bontrager R3 25mm tires, which work out at 29.5mm when mounted on the rims.
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I just checked and with the GP5000s (25mm, measuring ~28), there is 6+ mm of clearance everywhere, except the chainstays where clearance is right about 5mm. So you are probably fine to run the 25mm R3.
#8
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Yeah, given the 31mm external width, 29.5mm tires is just about right for the rule of 105.
I just checked and with the GP5000s (25mm, measuring ~28), there is 6+ mm of clearance everywhere, except the chainstays where clearance is right about 5mm. So you are probably fine to run the 25mm R3.
I just checked and with the GP5000s (25mm, measuring ~28), there is 6+ mm of clearance everywhere, except the chainstays where clearance is right about 5mm. So you are probably fine to run the 25mm R3.
#9
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I had a look at my frame when I got home and I can fit a 8mm Allen key either side of the rim, so there's about 16mm spare width between the chain stays. I believe the DT Swiss R470db rims I have at the moment are 23mm external width, making a total spacing of 39mm between chainstays at the rim.
At the apex of the tire, there's a total width of approx. 36mm, which obviously increases as you go further towards the rear hub; that's with a more rounded profile than the Bontragers will produce.
Mathematically, they will fit.
At the apex of the tire, there's a total width of approx. 36mm, which obviously increases as you go further towards the rear hub; that's with a more rounded profile than the Bontragers will produce.
Mathematically, they will fit.
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