V20c tire clearance and wheel sizes

[Braulio]

¿Has anyone tested the maximum tire clearance of the V20c? 38-622 "might be possible" according to Cruzbike. Wondering whether this is just a conservative estimate. A longer chainstay could potentially allow for more tire clearance if the fork isn't the bottleneck. That being said, a longer chainstay decreases tire clearance from the chain in the lowest gear(s). ¿And has anyone tested smaller wheels on the V20c? Wheel size should have a similar effect to chainstay length. Smaller wheels should allow for more tire clearance from the frame but less from the chain at the lowest gear(s).

 

[BJ686]

Did you mean 32-622? If so, I have been wondering this too. See below excerpt from the blog....

• Cruzbike V20c Racing Bike - 700c wheels and can probably go to 32c (not sure why anyone would do that though I would say 28c is typical max for a bike meant for speed/racing)

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[Braulio]

Did you mean 32-622? If so, I have been wondering this too. See below excerpt from the blog....

• Cruzbike V20c Racing Bike - 700c wheels and can probably go to 32c (not sure why anyone would do that though I would say 28c is typical max for a bike meant for speed/racing)

Bicycle tire sizes tutorial and what tire and wheel size ranges fit each Cruzbike recumbent road bike model

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The response I got from Cruzbike: "A 32C tire will fit comfortably - it might be possible to go to a 38c but not sure in a 700c why you would go that large. 32c might be about the widest realistically usable on this race platform."

 

[chicorider]

I'm running 30c on my V20c, with no fit issues. They roll fast and comfortably I wanted 28c, but could not find what I was looking for at a reasonable price, but the 30's were available and reasonable. If 28 is the new 25, then I figure 30 may as well be the new 28. 32c, while it should fit easily, starts to seem like a bit overkill for the V, in my opinion (and opinions, of course, will vary).

 

[Henri]

To the "why?": Not everyone buys a fast bike for racing (only). I want to be as fast and efficient as possible when I go somewhere, but that does not mean I never want any comfort. A 28mm tire for smoothest streets and a thicker one for somewhat less smooth rides would make it more versatile. Say one road and one gravel wheel set.
Would very much be interested what tires might really fit on a 28" or 27.5" or 26" wheel. (No smaller though)

 

[M.J]

Modern testing shows that wide tires aren't slower than narrow ones. Narrow, hard tires "feel faster", but aren't anywhere besides a velodrome. If they made a Conti GP5000 in 700c x 40mm (and they will, or maybe a GP6000), it would be just as fast as one in a 28mm.

 

[3bs]

also depends on rim. i run g one pros in 28 on renyolds assaults, and have gotten g one speeds in 30 on the bike, but thats max

 

[Enid]

On a modern 19mm internal diameter rim, 28mm Schwalbe Conti Grand Prix 5000 S are about 26mm, the 30mm are actually 28mm when measured. The size gets smaller as the rim gets wider. The old ones were more true to their stated size.

32mm has been tested to be slower than a 28mm when fit to a wheel that is made for a 28mm tire when you ride very fast, even though the CRR is lower on the wider tire on average tarmac. Surprise surprise. But a wider tire will roll better and may be roughly as aero if mounted on the right rim.

 

[DavidCH]

Well, it seems the pros have a thinner tyre up front so why not on a vendetta.

 

[Mathew Fy]

Well, it seems the pros have a thinner tyre up front so why not on a vendetta.

I’ll speculate. Compared to diamond frame riders:
-much of our leading wheel is In turbulent air
-our comfort is significantly impacted by the front wheel
-our margin of safety is improved from reduced pinch-flat and better grip of wider tires

 

[chicorider]

My purely anecdotal experience: I went from 20.5mm internal rim spacing with 25mm Scwhalbe Pro Ones on my V20, to 21mm internal rim spacing (so about the same) with 30mm Pro Ones on my V20c. Both bikes are wicked-fast, with the V20c edging out the V20 by a slim margin, which I attribute mostly to my feet being about three inches higher than before because of a longer chain stay.

I don't know how those wider tires play into, or perhaps against, this small speed boost, but I can say for certain that the ride is noticeably smoother, more comfortable and confidence-inspiring. If I had access to a wind tunnel and determined that these wider tires were fractionally slower on paper, I'd stick with them because the ride quality bump is worth it.

 

[Braulio]

On the stock Q45 wheels with rims of an approximately 16-millimeter internal width (22-millimeter external width), 50-584 tires fit in the rear but not quite in the front. The bottleneck is the [stock] chainstay.

 

[Braulio]

Continuation:

 

[Henri]

Should have looked it up: I didn't realize that 50 wide on a 584 rim is already a bit more circumference than even 32 wide on a 622 rim! A dream in the back and way closer to comfortable in the front than I expected! I might be looking for new wheels soon.

 

[Braulio]

Should have looked it up: I didn't realize that 50 wide on a 584 rim is already a bit more circumference than even 32 wide on a 622 rim! A dream in the back and way closer to comfortable in the front than I expected! I might be looking for new wheels soon.

¿Is it? I figured 50 × 2 + 584 = 684, whereas 32 × 2 + 622 = 686. The "× 2" is accounting for the tire being on both ends of the wheel diameter.

 

[Black Hawk Down]

¿Has anyone tested the maximum tire clearance of the V20c? 38-622 "might be possible" according to Cruzbike. Wondering whether this is just a conservative estimate. A longer chainstay could potentially allow for more tire clearance if the fork isn't the bottleneck. That being said, a longer chainstay decreases tire clearance from the chain in the lowest gear(s). ¿And has anyone tested smaller wheels on the V20c? Wheel size should have a similar effect to chainstay length. Smaller wheels should allow for more tire clearance from the frame but less from the chain at the lowest gear(s).

The rear tire can barely handle two inches. I wanted 2 inch Schwalbe Mondales on front and back so I swapped the front fork on my V20 with an S40 fork. It works great. Note that I'm running 26 inch wheels, which gives a bit more width.

 

[Black Hawk Down]

To the "why?": Not everyone buys a fast bike for racing (only). I want to be as fast and efficient as possible when I go somewhere, but that does not mean I never want any comfort. A 28mm tire for smoothest streets and a thicker one for somewhat less smooth rides would make it more versatile. Say one road and one gravel wheel set.
Would very much be interested what tires might really fit on a 28" or 27.5" or 26" wheel. (No smaller though)

I concur. I use my Vendetta as a fun road bike but have modified it for comfort with fat tires and a Thor Carrier seat. I also put a 1x12 Sram Eagle AXS drive train on it to get low gears. I have no interest in racing and the S40 is just too uncomfortable (recumbutt). I hope to do some credit card touring with my V20 using a trailer.

 

[Henri]

Is it?

Hmmh. I always only look at the circumference in www.Ritzelrechner.de XD
32-622 is listed as 2170mm and 50-584 as 2175mm. No Idea how they come to those numbers and what rim widths he assumes us to use and what rim width he assumes the label on the tire to be based on. Probably this is rooted in the stated width of the tire not being really accurate to real world use and only loosely correlating with tire height. Some tires with same stated width can measure really different when put on the same rim.
It does actually look like you have a little more height clearance than I have with a 32mm tire, but I have a rim on the far wide side for a 32mm tire. But how ever you look at it, those diameters/circumferences are damn close!
In a swappable-wheelsets-scenario maybe it would be better, if the wider tire has a bit smaller circumstance, so that gearing is lower because you will ride slower, because you ride on worse roads and a bit more aero drag. If 50 in the front is too tight, the resulting 40-45 would be a bit smaller, so it does that a bit.

 

[Braulio]

Hmmh. I always only look at the circumference in www.Ritzelrechner.de XD
32-622 is listed as 2170mm and 50-584 as 2175mm. No Idea how they come to those numbers and what rim widths he assumes us to use and what rim width he assumes the label on the tire to be based on. Probably this is rooted in the stated width of the tire not being really accurate to real world use and only loosely correlating with tire height. Some tires with same stated width can measure really different when put on the same rim.
It does actually look like you have a little more height clearance than I have with a 32mm tire, but I have a rim on the far wide side for a 32mm tire. But how ever you look at it, those diameters/circumferences are damn close!
In a swappable-wheelsets-scenario maybe it would be better, if the wider tire has a bit smaller circumstance, so that gearing is lower because you will ride slower, because you ride on worse roads and a bit more aero drag. If 50 in the front is too tight, the resulting 40-45 would be a bit smaller, so it does that a bit.

2170 millimeters is like the height of a basketball player. ¿How wide are your rims? Mine are about 22-millimeters externally.

 

[Henri]

2170 millimeters is like the height of a basketball player

Well, that's circumference. More than three times the diameter.

How wide are your rims

26mm internally, 31mm externally (on the outside edge. Does bulge out a bit over the rest of the shape. They are rated for tyres 31mm to 60mm. (I have a table that says this rim width should allow more, but they will have their reasons.)
I got these:

https://www.nextie.com/gravel-six-spoke

I was ordering there anyway and most other trispokes and such were not designed for anything more then 28mm.