radpilot

Hello, I have a Kona Dew Plus 2012 that has a Kenta 700x35c tyre.
Because I have light CTC (carpal tunnel syndrome) in both hands I want to increase the tyre size to make the ride more comfortable.
I want to try the new Schwalbe Marathon E-Plus tyres.
Up to which size from the following would the frame accommodate?

700 x 38C

700 x 45C

hokiefyd 

Hello, radpilot . Do you have a specific need for the strong puncture resistance offered by the Marathon Plus series? I ask because the ride quality of these types of tires is generally lower than a tire designed to be light and supple. Going to a larger size will help, but the firm ride quality of the tire will offset that somewhat. If you don't have a specific need for strong puncture resistance, going to a larger size and a more supple tire should make a good difference for you.

Crankycrank

What tire pressures are you running now? Your Kenda's list a low of 50 psi and you could probably go a little lower than that depending on your weight. Just lowering the pressure can have a big effect on comfort as long as it's not too low that you risk denting your rims when hitting potholes and such. To check if a wider tire will fit just measure how much clearance you have with the current tires and do the math. Actual tire sizes can be a little different between makes and models but if you have plenty of clearance it won't be a problem.

fooferdoggie 

for sure they are harsh and thats being kind.

ThermionicScott 

You probably have a fit problem rather than a tire problem. Make sure you aren't holding your arms straight and locking your elbows when you ride.

E-bike specific tires likely have extra reinforcement to cope with constant and higher torque than humans generally put out, so I would expect the opposite of comfort from them.

That said, the stock tires look pretty heavy and slow from the specs (685g and 22TPI), so you certainly have my blessing to upgrade to something that rolls better.

JanMM

I replaced the original Bontrager tires on my wife's Trek e-assist bike last fall with the same size (622-47/700-45) Schwalbe Marathon E Plus. Online purchase and was surprised at how much more robust they are. Plus: Not expecting to have to deal with punctures or tire damage. Con: Heavy, rugged, stiff. E-assist minimizes extra weight penalty and rolling resistance. No complaints about increased harshness.

radpilot

Thanks for the reply Hokiefyd
You are right, but I was thinking of puncture resistance because of the state of the roads over here and going over some light dirt roads.

radpilot

I usually go initially with 80 PSI and reinflate when I see that the tyre needs air.
So, say I measure X mm clearance at the worst case how would I know how much bigger tyres I could fit?

radpilot

Any suggestions then for a better tyre than the ones I have that has some puncture protection and can go over road and light dirt roads when commuting?
I understand now that Marathon E-Plus are geared towards ebikes and are heavy and harsh.
What about normal Marathon or Marathon Plus?

radpilot

Kona tech replied to me. But going only from 35c to 37c looks too little compared to the clearance I see with my own eyes.
"Hi, our sight unseen max tire size for that fork is 37c. Larger may fit but they need to be checked hands on. All tires can have a hop or a wobble that will mean if a bigger tire with a larger runout are installed they will rub under load.



Happy Trails! "

Crankycrank

Try running 50psi and see how you like it. Nothing to lose by trying. If Kona is saying a 37mm or larger will be iffy believe them. As mentioned, the actual tire size isn't always the same as what's on the label and can vary enough between brands and models that if you think it's close when buying it could easily end up being too large. Also consider the actual outer diameter may end up being too large to clear your brakes or frame if it's already a close fit. For good reviews on some of the Marathon versions and other brands this site gives some info on ride quality and puncture resistance and gives some actual measurements you can use to determine actual tire size. Doesn't cover every tire available but a pretty good amount. Bicycle Rolling Resistance | Rolling Resistance Tests

sch

Wow! 80 psi in 35mm tire certainly would be more comfy at 50-60 psi. I run 90-95 psi in 23 mm tires and find that adequate.
80 psi in 35mm would be rock hard and as crankycrank points out your frame will not allow much larger. 38 'may' fit or not
and tire to tire variance can be a factor (yrs ago we had 25mm Pro4 Michelins that actually measured 28mm on the tandem).
Major assumptions here that the OP is under 200# in weight or not much over.

GamblerGORD53

I bought a pair of those E-plus tires last year, but not used yet. They are actually supposed to be less stiff, more grippy and a bit longer lasting.
I may not use them this year either. The 15% recycled tire crap they put in them now is a really stupid idea, IMO.
70 psi air is good for these 36 mm tires.