Monstermash

Hey guys,

I'm hoping there is a Fastroad owner here that can answer a question for me. After seeing my Anyroad with the flatbar conversion my buddy wants to buy a Fastroad. I know the bike comes with 28mm tires on it but we were wondering if anyone has fitted anything larger on it. If so, how large were you able to go without any clearance issues?

If no one has tried anything larger on their bike, could someone please post a photo of the clearance with the stock tires on it. If you could take a few photos of the clearance near the rear stays that would be appreciated.

Thanks in advance!

irmd

one of the members wrote on this thread that they put 38c on. maybe give him a shout?

https://www.bikeforums.net/recreation...comax-1-a.html - towards the bottom of the thread.

Pistard

looked at that today, does not look like more then 32 that will fit.

RickGr4

On my 2015 SLR1 (I no longer have it) there was plenty of room in the front to go with a larger tire however the back is a very different story. The mount hole for the rear fender is not far away from the tire. I would think a 38 on the back is possible but it will get very close to the fender mount hole.

I just checked my current 2016 CoMax 2 and there is noticeably more room for a larger back tire. I would be careful when comparing the SLR1 to the CoMax 2 frames. The dimensions do not appear to be the same.

hcgaloi

I just bought a 2016 Fastroad SLR1 few days ago. I asked the same question and LBS said 32 would be the largest.

PDKL45

Sorry to Zombie this thread, but has anyone seen the WTB Horizon "road plus" tire (https://www.wtb.com/products/horizon)? It's a 650B x 47 tire that is intended to be used in road frames. The outer diameter is roughly the same as that of a 700x23/25c tire, but it is significantly fatter and follows the trend for fatter tires and lower pressures (https://janheine.wordpress.com/2015/...re-revolution/).

While a 700x32c may be the biggest 700C tire that would fit a Fastroad, I am wondering if the WTB Horizon would fit? It would give the Fastroad a look very similar to OP's flat bar Anyroad.

prj71

It's a 650b tire therefore it will not fit on the Fastroad rims.

If you bought a wheelset to fit those tires, the 47mm width would be too large to fit between the fastroad chainstays.

PDKL45

Right. You need a whole new 650B wheelset, but with disc brakes it is a simple matter.

The width of the Horizon is the real issue, but I am not convinced that it would not work. The fatter part of the tire is moved rearward for lateral clearance, so I think that if 700x32c would fit then there is a real chance that the Horizons would also fit.

*Edit: I saw a Fastroad SLR 1 at a Giant store today. Getting a 47mm tire in there might be problematic to say the least. prj71 has a good point, although a tire like a Compass 650x38 Loup Loup Pass would probably work.

prj71

The FastRoad is nothing more than a road bike with flat bars instead of drop bars...which is why there will be a tire clearance issue. If you want more tire clearance you would have to look at the Giant Anyroad or Giant Revolt.

PDKL45

Surprisingly enough, the Anyroad I also saw yesterday didn't actually have that much more clearance in the chainstays, based on an eyeball measurement alone. However, after reacquainting myself with one of the articles on 650B conversions I had read in the past, I saw that it was a 650x38B tire (650B Superbike).

It would not be for everyone, but for those determined to shoehorn a larger tire into an existing frame, the option is there.

nickwalt

Did anyone find a satisfactory conclusion fitting a larger tyres? Any changes to the 2019/2020 models?

I want to run larger tyres for city use and find it odd that the Fastroad isn't designed to be more flexible with tyre widths. At least more so than a dedicated drop bar road bike.

If the rear could comfortably take a 38mm tyre I would swap out the front fork for one that could fit 38mm.

Any thoughts?

nickwalt

Just spoke to a LBS and they concluded that a 38mm tyre will fit the Fastroad SL 1. They even suggested that a 40mm might fit without scraping.

I'm going to request a test ride on 38mm and/or 40mm tyres at this store so will report back here.

pcunite

How did it work out?

nickwalt

If I recall correctly the 38mm fit ok. I liked the bike but ended up with the Giant TCX Cyclo-cross. It came with 33mm tyres and they work well for light inner city use.

I found the TCX's dropbar to be a lot more engaging than the flatbar of the Fastroad. The TCX has wider bars than a normal dropbar.

I recommend riding the Fastroad with the 38mm tyres. I think 38 is the largest that will fit. Cheers.
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