# Tire clearance on R3 and RS? Possible to run 25's?



## RJP Diver

I'm assuming shouldn't be a problem - thoughts?


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## Clay L

i've ran 25s on my RS without any issues. i think the R3 can do the same.


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## porterhouse

What year R3? Can't speak for the earlier R3 but there is little room on the rear of the current R3/R5. I suppose if you had really stiff rims it might work but otherwise the 25c tires will definitly rub the seat stays under a load.


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## AC0

No problem with a 2010 R3, Ambrosio Excellence rim, Conti Gatorskin 25mm tire.

AC


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## giro_man

Not all 700x25 mm tires will fit a 2009 Cervelo RS. Vittoria Rubino Pro in 700x25 will fit but Continental Grand Prix 4000 in 700x25 will not fit.

At the forum at www.cervelo.com, the assumption is that tire size can be a problem.


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## tdietz87

Okay, here are images of my 2011 Cervelo r3 with Conti 4000's 23mm. The seat stays are the only area where the frame is close enough to matter. I've never ran 25's, so I am unsure how much clearance you need.

For reference there is about twice the amount of space from my brake pads to rim, as there is seat stay to tire.

Hope this helps.


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## MisterC

So, when they run 27mm tires in Paris-Roubaix they are on custom frames? I thought the Cervelo claim to fame was that all of their riders are on stock frames.


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## burkeqc

Looking at the picture, the slightest out of true condition for the back wheel and/or lateral movement will end up with the tire rubbing on a carbon stay. Occasionally gravel with tar with stick will to a tire on the side before being peeled off. . I would say no.


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## RJP Diver

RJP Diver said:


> I'm assuming shouldn't be a problem - thoughts?


As an FYI to anyone who might dredge this thread, I am able to run Gatorskin 25's on my new 2011 R3 with no problem at all.

Thanks for all who responded!


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## Cut.Aussie

I have bought a 2011 Cervelo RS framset and was surprised to see so little clearance between the centre of the tread and the middle of the fork, I haven't put a feel gauge in there but I'm guess about 35 thou.

Dura-Ace wheels with Continental GP4000S/25 types at 110psi.

Agree that's not a lot of clearance for junk stick to the tyres, thinking of bonding some 25 thou brass shim stock into the top arch of the fork dropouts so the wheel sits 25 thou lower increasing that air gap somewhat.


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## Gimme Shoulder

Yep. Some 25mm tires barely clear. The 25mm Vittoria Diamante Pro Lite that came with my 2008 RS only had 1/16" clearance under the fork crown. Debris did get in there and scraped up the underside of the the fork.


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## Cut.Aussie

Well I had a couple of weeks riding my new RS with Conti 25's and I getting slightly annoyed with the sound of every little bit of road junk hitting the forks so I have just ordered a single 23 tyre and will try running a 23 up front and a 25 on the rear to better support my weight and protect the spokes better from breakage.


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## RJP Diver

Cut.Aussie said:


> Well I had a couple of weeks riding my new RS with Conti 25's and I getting slightly annoyed with the sound of every little bit of road junk hitting the forks so I have just ordered a single 23 tyre and will try running a 23 up from and a 25 on the rear to better support my weight and protect the spokes better from breakage.


Interesting/surprising that the fork on the RS would seem to have less clearance than the fork on the R3. I have Shimano RS80s on my R3 and run Conti Gatorskin 25's and have no problem with road junk hitting the fork... and my typical ride involves miles of unpaved roads as well.


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## brawlo

Does anyone know how 23mm rims affect the clearance issues? I'm still tossing up between the R3 and S2, just waiting to get the last bit of money together. I was leaning towards the R3, but I have a set of Ultegra/Velocity A23 wheels to go on it for training/racing until I can get something better for race only. I will still use them to train on. I have a pair of 25mm Conti GP4000 tyres to go on them. Might have to ditch them by the soiunds of it though......

At 6'5", I don't get to go out and try them both before purchase. I'm going to have to make my decision based word of mouth and what I read.


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## porterhouse

Without thinking it through, I bought 3 25c GP4000 tires with the intention of mounting them on a set of C24 Dura Ace rims and using them on my R5. Figured it would be a good comfortable wheelset for long days in the saddle. Unfortunately, there was minimal clearance so I mounted up the same tires on a 19mm width rim hoping I could use the tires on some different rims. Unfortunately, there was virtually no difference in tire width. 

Cant remember the exact widths and there is some variation in width in the tire so it was hard to come up with exact numbers, but after doing three or four measurements at different spots on the tire, I would say there was less than a millimeter differerence in width.


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## Hughsdad

I have used Gatorskin 25s on the rear of my 2011 RS, with no problem at all. But I've only had 23s on the front. There is very little clearance on the front.


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## mahoba

I use Conti 4 Seasons in 25 on my RS. No problem.


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## MattSoutherden

It's a little surprising that the Funda fork specced has such tight clearances. I generally run Vittoria open Pave 24mm on my RS which are fine. I have also run a 25 gatorskin up front and a 28 in the back (rear with an A23 rim). The crown clearance on the 25 was just about ok, but only just.


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## Sudor

*R3 wheel/tyre to seat stay clearance tolerances*

My 2010 Cervelo R3 was replaced under warranty (bottom bracket stress cracks) with the new geometry 2011/12 R3. I run Shimano 7900 CL 24's with vittoria 700x23 open corsa evo CX tyres. On my very first ride I found that the tire was rubbing on the non drive side seat stay when breaking. 

The clearance is almost non existent on the non-drive-side indicating an incorrectly ground rear wheel drop outs. My LBS initially thought this was caused by out of true wheel. However, upon trying out the fitting of two different (jig confirmed) true new wheels this confirmed that the the wheel to seat stay clearances are out of true effectively eliminating non- drive- side to seat stay tolerance and equally increasing the drive side wheel to seat stay tolerance by about 4 mm. To my mind the wheel to seat stay tolerance should be equal on both sides of the wheel - does anyone have experience or thoughts of this of this issue?.


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## RJP Diver

Sudor said:


> To my mind the wheel to seat stay tolerance should be equal on both sides of the wheel - does anyone have experience or thoughts of this of this issue?.


Interesting - both sides are equal on my 2011 R3 running Shimano RS-80's


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