# Tire clearance '20 Domane SLR vs '18 Boone



## Emilio700

Last two years I have swapped the 1x for 2x on my 2018 Boone after cross season. Raced Crusher in the Tushar, Dirty Kanza, Belgian Waffle Ride on the Boone. Love the front and rear IS decouplers, my primary reason for choosing these. The Boone has pretty aggressive geometry. Low HT, long TT that suits me. Been looking for a new gravel bike so I don't have to mess with taking apart the Boone every year. Checkpoint is nice but geometry is too upright for me without needing a stupid long stem and dealing with toe overlap.. plus no front ISO.

Standard Domane SLR geo is what Trek calls "Endurance". Very upright and not suited for a racer in most cases. The longer, lower "Pro Endurance" geo is only available through Project One so that's what I'm ordering. Custom paint is a bonus

So to the point. Measured tire clearance at widest point on 2020 Domane SL6 and my Boone. A bigger size tire will have its widest point slightly higher than a smaller tire so factor that in.

2020 Domane SL/R
Fork ~55mm
Chainstay ~54mm

2018 Boone
Fork ~51mm
Chainstay ~46mm

I ran 36c IRC Boken on 21mm internal wheels that ended up about 37mm wide. Tried two different 38c tires on the same wheels and the Boone and didn't have enough room. Hard cornering or acceleration would cause a tiny bit if rub, leaving witness marks on the stays. Having worn through the carbon on other frames by trying to stuff too wide a tire in their, I'm a bit cautious now.

Anyway, the new Domane SL/R easily has enough clearance for any 38C (as claimed) and will likely fit some 40's depending on brand and rim internal width. That's a gravel bike friends.


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## M-theory

Emilio700 said:


> Anyway, the new Domane SL/R easily has enough clearance for any 38C (as claimed) and will likely fit some 40's depending on brand and rim internal width. That's a gravel bike friends.


But it's still not a gravel bike... because... every bike comes with a safety rating with regards to the road surface it can be used upon SAFELY. The Domane would still be rated 'Condition 1', meaning 'for paved road use only'. That means the fork and frame strength were not designed to the strength specifications required of an off-road bicycle.

The Boone and Checkpoint ratings would be 'Condition 2', allowing for un-paved road conditions.

The number is located on the lower part of the down-tube, near the bottom bracket.


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## Emilio700

Good point. One wonders just how delicate Trek would build a frame with twin ISO decouplers and accepting such huge tires. The now-discontinued Domane gravel which was not really a gravel bike, was probably a condition 2 frame set. Reviews of the new Domane SL all surprised and how heavy it is. I fired off an email to someone I had been speaking to at Trek, asking to confirm which condition type it is.


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## M-theory

Emilio700 said:


> Good point. One wonders just how delicate Trek would build a frame with twin ISO decouplers and accepting such huge tires. The now-discontinued Domane gravel which was not really a gravel bike, was probably a condition 2 frame set. Reviews of the new Domane SL all surprised and how heavy it is. I fired off an email to someone I had been speaking to at Trek, asking to confirm which condition type it is.


Yes, it's an easy criteria to overlook or forget, since one would assume the bike frame is rugged with such wide tire clearances. But you really can't assume anything, especially if you intend to do some serious racing off-road. 

If you don't mind, please keep us posted on what Trek's response is. I think it's important info for anyone reading this thread to know. Thanks.


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## Srode

Using a -17degree stem will help make bikes more aggressive if that's all you don't like about the checkpoint. Personally, being able to fit a 38mm tire isn't a great gravel bike if you get into muddy conditions. The new standards are more room for 45 to 50mm tires which means you can run 40mm with lots of clearance for mud.


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## Emilio700

Srode said:


> Using a -17degree stem will help make bikes more aggressive if that's all you don't like about the checkpoint. Personally, being able to fit a 38mm tire isn't a great gravel bike if you get into muddy conditions. The new standards are more room for 45 to 50mm tires which means you can run 40mm with lots of clearance for mud.


You missed some important details. Checkpoint does not have front ISO. There is a vast difference between the pro endurance and standard endurance geometry. Even with the funky negative rise stem I would never get my bars in the right position and the top tube is still way too short. I just don't see a reason to compromise who win the correct geometry is available for me.

As far as the mud, I would never run a 40c in the mud anyway. Me this is a gravel race bike. I understand it might not work for everyone as a gravel bike but it does for me.


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## Srode

I saw that you were looking for something with the front ISO. You could always use a Lauf fork if that front end compliance is important to you. The Domane SLR isn't a gravel bike though, I would suggest looking beyond the Trek offerings to see if someone else doesn't get you closer to what you are looking for, the ISO speed is neat, but it's not the only way to get compliance and there's probably a reason Trek didn't put it on the Checkpoint. 

As far as the mud clearance and tire choice, there are times when the majority of a course is bone dry yet several miles are muddy, especially on long races. Personally I choose a tire that will do well for the majority of the course and not the few miles that are muddy.


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## Emilio700

According to Trek the reason they did not put ISO on the checkpoint is cost. 

Zero interest in the undamped Lauf fork. Ride one and try to accelerate hard out of the saddle. Yuck.

54mm tire clearance is plenty for what I will need on my race bike.

Wasn't really looking for suggestions or alternatives just sharing


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## Emilio700

Ofishul reply from Trek:

_"You certainly could use the Domane for either purpose (gravel racing) as it has clearance in the frame for larger tires. However, the bike we designed for condition 2 riding is definitely the Checkpoint."_

That's good enough for me. Their condition 1 bikes are designed for 275 lb riders. Their 170 lb world tour riders whack into 2" cobblestones at 30mph on 28c tires. At 159 lbs, I'm not too worried about fatigue life with 38c tires.


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## M-theory

Emilio700 said:


> Ofishul reply from Trek:
> 
> _"You certainly could use the Domane for either purpose (gravel racing) as it has clearance in the frame for larger tires. However, the bike we designed for condition 2 riding is definitely the Checkpoint."_
> 
> That's good enough for me. Their condition 1 bikes are designed for 275 lb riders. Their 170 lb world tour riders whack into 2" cobblestones at 30mph on 28c tires. At 159 lbs, I'm not too worried about fatigue life with 38c tires.


Thanks, it's good to know they have confidence enough not to issue a warning against gravel racing. As you say, a little less tire pressure goes a long way in reducing fatigue. The Trek website literally has videos showing Domane riders on gravel roads. So yeah, should be good.


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## Emilio700




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## wesmeyer11

Emilio, 

I have been thinking about going this route. Would love for you to update us on how this is working out! Thanks.


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## Emilio700

wesmeyer11 said:


> Emilio,
> 
> I have been thinking about going this route. Would love for you to update us on how this is working out! Thanks.


Working perfectly, love the bike. More detailed thread: https://forums.roadbikereview.com/gravel-bikes/2020-domane-gravel-build-371103.html

Any specific questions?


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## wesmeyer11

I guess my main concern would be how the front and rear iso speed are holding up to the more extreme demands of gravel riding. I don’t know much about the service interval or the need to replace any parts within. I would imagine that the maintenance increases due to harder riding on trails.


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## Emilio700

wesmeyer11 said:


> I guess my main concern would be how the front and rear iso speed are holding up to the more extreme demands of gravel riding. I don’t know much about the service interval or the need to replace any parts within. I would imagine that the maintenance increases due to harder riding on trails.


Good question for the build thread, so others can see it. Same basic ISO as the Boone, which is their Pro level cyclocross frame, of which I also own and race.

Think about a 175 lb monster like Fabian Cancellara hitting the Arenberg Forest (cobblestones) at 25-30mph on the 2012 bike. 8 years worth of improvement. I think its safe 

From 2012 https://www.youtube.com/watch?v=sB8jJH-mumY


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