My frame (Felt B12 2016) will only let me run a 23mm tyre on the rear due to clearance issues, but I can fit a 25mm on the front with no problem, so this is what I have been doing. I run a slightly lower pressure on the 25mm (95 and 105psi on the rear). My question is , is this optimal or would I be better running 23mm on both? The wheelset is really designed for 25mm, so I think the answer may be to keep what I am doing and just take the aero hit on the 23mm, but would like some thoughts from those that know better. Tried some searches, but no real examples of people running this set up that I can find.
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Re: Wider tyre on front than rear? thoughts? [jubbely]
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I run 28 front 25 rear at like 70 and 80psi respectively due to similar frame clearance issues.
I've been doing it for years as we had 2 or 3 extra 28s sitting around and wanted to see where they would fit so I could use them. I've never had any kind of issue at all and I'm sure my wheels aren't optimized for 28s.
Maybe one of these years Ill be able to get into a disk frame and can run 28s on both ends. Until then, I won't be changing anything about my setup.
I've been doing it for years as we had 2 or 3 extra 28s sitting around and wanted to see where they would fit so I could use them. I've never had any kind of issue at all and I'm sure my wheels aren't optimized for 28s.
Maybe one of these years Ill be able to get into a disk frame and can run 28s on both ends. Until then, I won't be changing anything about my setup.
jubbely wrote:
My frame (Felt B12 2016) will only let me run a 23mm tyre on the rear due to clearance issues, but I can fit a 25mm on the front with no problem, so this is what I have been doing. I run a slightly lower pressure on the 25mm (95 and 105psi on the rear). My question is , is this optimal or would I be better running 23mm on both? The wheelset is really designed for 25mm, so I think the answer may be to keep what I am doing and just take the aero hit on the 23mm, but would like some thoughts from those that know better. Tried some searches, but no real examples of people running this set up that I can find.How fast are you going?
What's the road surface quality?
How much do you weigh?
What kind of wheelset and rim shape?
Pack riding or TT?
There's so many 'it depends' but the long and short is between 25 and 23 it's a couple watts max. In theory, as you go faster, the aero benefits of the 23's smaller frontal area will outweigh the lower RR of the 25 (on a normal road). This crossover is around 25-30mph from what i've read, but again that depends on the shape of the rim.