Tires for Sirrus 4.0
#1
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Tires for Sirrus 4.0
The bike came with Specialized RoadSport Reflect tires in 700X32c. The recommended pressure is 85-90 psi, and I generally run them at 90.
I'm considering whether a different tire will increase the bike's performance in a noticeable way. Of course, I can't instrument test so it would all be subjective anyway. But, I'm wondering if there may be any obvious performance differences if I were to change to something like the Bontrager AW2 Hard-Case Lite or Continental Grand Prix 5000.
My riding is road or paved trail. The current size is fine, and I see no reason to change that. I'm also fine with running tires at high pressure, and I'm not particularly interested in a softer or more compliant ride. I'm mainly interested in adding some speed, efficiency, and responsiveness.
My last bike was a mountain bike, so I don't have any past experience with road/hybrid tires.
Interested in any thoughts, opinions, and guidance.
I'm considering whether a different tire will increase the bike's performance in a noticeable way. Of course, I can't instrument test so it would all be subjective anyway. But, I'm wondering if there may be any obvious performance differences if I were to change to something like the Bontrager AW2 Hard-Case Lite or Continental Grand Prix 5000.
My riding is road or paved trail. The current size is fine, and I see no reason to change that. I'm also fine with running tires at high pressure, and I'm not particularly interested in a softer or more compliant ride. I'm mainly interested in adding some speed, efficiency, and responsiveness.
My last bike was a mountain bike, so I don't have any past experience with road/hybrid tires.
Interested in any thoughts, opinions, and guidance.
#2
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For your criteria / objectives -- speed, efficiency, responsiveness -- I think Conti GP5000 is worth considering.
Be aware they can be pricey compared to other road tires and they are not the most puncture-resistant.
But they're not delicate either. I recommend them, they can improve your ride in all ways you list above.
Be aware they can be pricey compared to other road tires and they are not the most puncture-resistant.
But they're not delicate either. I recommend them, they can improve your ride in all ways you list above.
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I will second the suggestion re. Conti GP5000s. If you want lower rolling resistance, better ride quality, and can live with reasonable puncture resistance, they are hard to beat. Also consider Specialized's Roubaix Pros in size 32: effectively, these are a much nicer version (suppleness; low rolling resistance; lighter) of what you (op) now have.
By the way, 90 psi is very high for a 32. Higher pressure does not = higher speeds (lower rolling resistance) on real-world roads. If you weigh anything under around 190 lbs, you might want to try lowering your tire pressures a bit.
By the way, 90 psi is very high for a 32. Higher pressure does not = higher speeds (lower rolling resistance) on real-world roads. If you weigh anything under around 190 lbs, you might want to try lowering your tire pressures a bit.
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Recommended pressure for the RoadSport is 85-95. I've been going for the middle of that, and it seems fine.
And, yes, I'm hitting scale at 190 right now. Would like to give up 10 of that.
And, yes, I'm hitting scale at 190 right now. Would like to give up 10 of that.
#5
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I have a Sirrus Sport that came with Nimbus 2's in 32. Upgrading to 28mm Conti 4 Seasons made a HUGE difference in feel and performance
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Thanks Laser! Can you describe the differences a bit?
Also, will a 28mm tire be a good fit on this wheel (as described by Specialized): 700C disc, double-wall alloy, 22mm depth, 21mm internal width, 28h
Also, will a 28mm tire be a good fit on this wheel (as described by Specialized): 700C disc, double-wall alloy, 22mm depth, 21mm internal width, 28h
#7
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Sure! The bike accelerates and climbs better because the tires weigh half as much as the Nimbus. There's also less rolling resistance because the 4 Season is a better tire. The Nimbus wasn't an off road tire but I can tell the difference between a 28 and a 32 when things get loose and sandy. Can I ride a 28mm off road, sure, but a wider tire is going to be a much better tool. However for the majority of my riding I prefer having a fast flat bar road bike since I'm on pavement and roads. If I lived somewhere that had an abundance of dirt roads and singletrack I'd probably go with something like a 32-35mm tire at a lower pressure
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Thanks for the feedback!
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I actually just bought the same bike from my LBS and have been debating on what to swap the RoadSport tires with. This has been super helpful.
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Switch out the pedals as well, as they are energy zapping. I went with the RaceFace AEffect and my wife put the RaceFace Rides on her 4.0. Huge improvement in both cases for not much money. She was skeptical when I told her that I wanted to change them. First ride and she told me I was right. Those are not words I hear very frequently!
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Interesting. I'll check those out too. My wife and I finally found and picked up some new bikes (as did everyone else in the world lol.) Still trying to get familiar with some things as this my first real bike since high school. It's been challenging to find info/forum posts on this bike (keep finding X4.0 info.)
On tires, I ride in and around the city so I've been debating between the Conti GP5000 and the Marathon Supremes. Im leaning towards the Supremes, but my use case/wants seems different than yours. Thanks for the recommendation!
On tires, I ride in and around the city so I've been debating between the Conti GP5000 and the Marathon Supremes. Im leaning towards the Supremes, but my use case/wants seems different than yours. Thanks for the recommendation!
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We'll have to compare notes some day.
You are right, information on these bikes is hard to find. The bikes are also hard to find around here. I drove 200 miles to buy mine since no one in DFW had it or anything comparable in size large at the time.
You are right, information on these bikes is hard to find. The bikes are also hard to find around here. I drove 200 miles to buy mine since no one in DFW had it or anything comparable in size large at the time.
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Sure! The bike accelerates and climbs better because the tires weigh half as much as the Nimbus. There's also less rolling resistance because the 4 Season is a better tire. The Nimbus wasn't an off road tire but I can tell the difference between a 28 and a 32 when things get loose and sandy. Can I ride a 28mm off road, sure, but a wider tire is going to be a much better tool. However for the majority of my riding I prefer having a fast flat bar road bike since I'm on pavement and roads. If I lived somewhere that had an abundance of dirt roads and singletrack I'd probably go with something like a 32-35mm tire at a lower pressure
Did a leisurely 4 miles this eve. So far so good. Nice upgrade!