mb2112

Anyone noticed the max tire size on Trek's site is shrinking? When I first looked at these it was 45c, then went to 40. Now it says 35. I have 37c WTB Riddlers and there's loads of room to go bigger.

Skipjacks

I feel like they aren't gradually changing to smaller and smaller forks.......

So yeah...that is odd

FlashBazbo

I just talked with Trek. The bike is the same 2019/2020. But Trek's legal counsel advised that, for regulatory reasons, the official capacity spec needs to change. I asked what would be dangerous about a 45mm tire that's not dangerous about a 35mm tire. They said that the CPSC calls for 6mm (1/4") of clearance between the tire and any part of the frame. With a 35mm tire, there's 4mm of clearance -- but . . .

It could be that the clearance issue isn't at the sidewall but between the tread and the seat tube or bottom bracket. The Checkpoint has the capability of moving the rear wheel up close to the seat tube. Could it be that a flexing Isospeed / seat tube could reduce the clearance to the rear tire and that the new spec allows for this?

EDIT: I looked at my Checkpoint again. The seat tube has a cutaway design to clear the rear tire, BUT . . . the front derailleur mounted on that seat tube hangs about 10mm farther back than the seat tube does. I'm guessing the point of interference, with the rear axle adjusted all the way forward, is with the derailleur.

I would never have bought a bike with a 35mm tire width spec. And certainly not with the 31mm max width it would take to get 6mm of clearance all the way around. (Of course, by these numbers, there would be -1mm of clearance on a 45mm tire, but . . . )
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Lava

I wonder if this explains the ALR/AL discrepancy in tire clearance, since the AL came out after the ALR and had reduced clearance?

Has anyone experimented with tire size on the AL this early in the game?

FlashBazbo

Since this is a safety issue, I wonder if Trek is going to issue a recall of all the bikes they sold using a claim that you could safely use 45mm wide tires. This leaves the impression of being a half-baked product that was rushed to market in order to avoid missing out on the gravel craze. The initial marketing claims were great. Now, they're walking them back. And 10mm of tire capacity is a pretty big walkback!

gus6464

That clearance thing makes no sense. Road bikes have razor thin clearance on the chainstays in relation to sidewall. The 6mm clearance is in relation to yolk where chainstay and seat tube meet and also along the entire seat tube. I am pretty sure the issue is with the isospeed moving the seat tube too much which could cause it to rub on a bigger tire.

I wouldn't even call the checkpoint a gravel bike anymore with a 35mm tire clearance. It's just another CX bike at this point.

This is what's listed on the 2020 so basically they making you use a specific tire so they can get by saying it can take 40c. That way if you have an issue and you not running that tire at 40c you out of luck.

Max tire size40c Bontrager tires (with at least 4mm of clearance to frame)

FlashBazbo

Yes, the new "spec" size 40c Bontrager on the website is something that changed either this morning or over the weekend. As of Friday, both on the website and in discussion with Trek's customer support guy, the spec was 35mm. This whole thing stinks.

If you wanted to unload your Checkpoint now, how much does this impact the value? Will any knowledgeable buyer trust it to handle more than a 35mm tire?

FlashBazbo

I complained to my LBS about the tire capacity issue last week. He tried several times on Friday to get an answer from Trek, without success. (Telephone tag.) He's a fairly large Trek dealer, so I would hope they'll eventually talk with him. Trek should have contacted its customers about this. It shouldn't have been something we "happened to notice" on their website.

I actually think the problem is front derailleur / rear tire interference when using bigger tires. But, either way, there's no excuse for this.

gus6464

There are many manufacturers that will list tire clearance whether you running 1x or 2x with 1x having the most. If Trek did this I wouldn't really fault them and would make sense so it's odd that they wouldn't if that was actually the case. How close is your 45c tire to the seat tube at the closest spot? Isn't the isospeed decoupler supposed to make the whole seat tube deflect back and forth?

FlashBazbo

I don't have a 45mm mounted now. But the front derailleur sticks back about 10mm farther than the seat tube does. And when the Isospeed seat tube flexes backward, the front derailleur moves back with it. (It's mounted on the seat tube.) My current 32mm tire fits beside the derailleur, but it appears that a 45mm wide tire would hit the front derailleur.

CodyDog

Wow! I was about to order the Checkpoint SL5 this week. I think this is a game breaker. I think I want a gravel bike that is capable of allowing a tire larger than 35mm. Bummer. Sad thing is I had to call attention to the change on Trek's website to two Trek dealers in Austin As of Saturday, they both thought a 45mm tire was usable.

mstateglfr 

Perhaps they are just offering along the lines of what competition offers? Are any mainstream(or even second ring) gravel bikes set up with dual suspension?

FlashBazbo

The Checkpoint has been removed from the Trekbikes.com website. At least temporarily, the Checkpoint (at least its page) appears to be dead.

And Customer Service says there will be no recall because the stock 35mm tires are perfectly safe. You bought based on that 45mm capacity claim? Buyer beware, sucka!

radroad

It seemed to be a very odd, halfhearted design. I'm sure they'll take a shot at it again: the gravel market is too significant to ignore. I guess they're flummoxed about how to build a gravel bike that doesn't cannibalize sales from their domane line.

mb2112

So just spoke to Trek about my Checkpoint and tire size. They say the max tire also depends on the frame size, so the derailleur location may be a factor. Either way, they say my 54cm SL5 will handle 45c tires. I have 37c WTB Riddlers on it now with loads of room to spare.

jwill911

I'm about to pull the trigger on a Checkpoint either sl5 or sl6. Wondering what folks are getting for discounts at their LBS. I like the price of the sl5 better but really like the black (only) color of the sl6 and do like Ultegra group set better. With a 15% off list I'm sold on the sl6. I have been a dedicated roadie for years but looking to venture out on dirt and gravel to expand my horizons. Both of my road bikes are Ultegra R8000 on the newer and 6800 on the other.
Thanks for any help.
John

CodyDog

I'm glad to hear what you said about talking to Trek. Was it a Trek dealer or Trek company? Did they say 54cm and larger?

Thanks.

Adrianinkc

mb2112

That's what the Trek rep said in a chat conversion from their website. I did't ask about 54c and up, but I'd assume larger frame = larger clearance.

Adrianinkc

I was told the change occurred because of a change in a standard on toe overlap that they had to make a change in tire size. Asked about the rear and they said legally speaking allow 6mm around the tire. This is what I got through the chat option on trek.com

jwill911

I managed to get 12% off the SL6 and 20% off misc accessories I bought. Came to just under $4000, w/ cages, rim tape, valves and can of goop to run tubeless and some other minor stuff. Funniest thing is I told my wife I bought the bike and she didn't even ask me how much it was. She'll see the credit card bill. It was in the warehouse same state so I should get it next week. I rode the SL5 for about 20 miles and liked it other than some minor fit issues but wanted Ultegra and didn't like the gray that much. The SL6 has a 20% setback on seat post instead of 10% and I need a 110mm stem instead of the 100 or 90 it felt a bit cramped in the cockpit.
John

fishboat

re: long term experience on a Checkpoint..search youtube for "ryan van duzer #lovecycles "

It's a summer of 2018, 34-episode ride from Astoria, OR to NYC. Both Ryan and Ali rode Checkpoints. Bikes seemed to perform well on road & gravel. Ali needed two front derailleur replacements during the trip for some reason..unknown why(other than shifting was an issue).

Chi_Z

that channel looks like is sponsored by trek, I would take what they say with a grain of salt

fishboat

It is what it is..take it or leave it..makes no matter to me.

softreset

Definitely sponsored by Trek. He got the bikes for free.