Rdmonster69

Hi all , Last week I bought a new Domane SLR 6. I am really pleased with the bike. I have a few questions. Some will probably be easy to answer. Before the questions I will say it is a major improvement over my previous bike in comfort and performance. I love my old bike and still am riding it but the difference is striking. OK ...A few questions.

1. The two bikes are very similar in weight. There is a major difference in speed. Any idea why? I can average close to 17 mph on the new bike over 25 miles....about 15 on the old one. Is it gearing, the wheels. Im at a loss because the weight is so close and I'm not really up on the technical bike stuff ... I can work on em and ride em but thats about it.

2. What size valve stem do I need. Weird question but I bought an 80 mm as a spare and it looks ridiculously long. I know It will work but figured someone here will know. The rims are deeper than I've had so I am not sure.

3. It pulls oddly to the left when riding no hands. I have to lean a bit to ride no hands. Figure it may be related to the disc brakes but they don't drag so ....my other bike dead straight. Its not a big deal as the new bike doesn't need to be ridden no hands often because my neck is much better on it.

4. Clamping in a work stand. The guy at the Trek shop made it seem like I would crush it if I clamped it in my stand. That sounds kinda bad. How do I work on this thing ? Its my first carbon bike so I'm a bit paranoid.

Thanks for looking. This site has been a nice find and being able to cycle after my accident has basically saved my life. My introduction thread details that mess. The new bike is amazing and I am still riding the old one so life is pretty good.

My bike area ....movie posters courtesy of my daughter.

biker128pedal

I have the stealth black color. Black is faster you know. Even for SL vs SLR.

Tube stem length for my cheapo Paradigms 25 Rims 37mm stem tubes that just work with my Bontrager pump. You have Aeolus 37 so my guess is 45 minimum. YO may have to settle for 60mm more common.

Tires. I found the 32mm R2s sluggish. You have tubeless R3s so better. Put a 25mm Conti GP5000 on the front and 28mm on the rear. But then I have a cheap SL6..

Stand. I was told the same thing about clamping. I had already had a Madone 5.0 so I was familiar with carbon. I just use the stand clamp to support the top tube with a cloth between. Then just use the adjustment knob on the clamp to gently hold the top tube. I need to ask the shop about the seat post. I think I saw then assembling and SL7 and clamped to the seat post. But don’t really have enough sticking out.

Why is the new Domane faster than the old bike. Well because it is new and new is always faster. 😀. The Domane is more aero. Better frame and the aero wheels. I had Aeoles 5s (50mm) on my Madone 5.0 which was a great improvement over the old Race rims. My SL6 is about the same as my old Madone so I thin a set of Aeolus 37s may be on order for me. I'd have gotten and SLR6 too if they had been available last July. Also the fit may help.

Enjoy your SLR6 and I am so jealous.

Edit: On the pull to the left. I noticed your brake lines and shifter cables are ties together under the stem. Mine are not. Granted from the Trek web site it looks like they are supposed to be tied together. But could be this and as said below the cables are causing the pull. I'd loosen them and see and happens.

cxwrench

Of course you don't want to clamp the frame, but you can definitely clamp the seat post or seat mast where they overlap. Why didn't you figure out what size valves you need when you picked the bike up? I'm guessing 60mm will do fine. I'm guessing that the 'pulls to the left' issue is one of the pieces of housing up front is pushing the bars off center.

GlennR

Wheels, quality of bearings and more efficient power transfer is why it's faster.

Valve stem.. ask the dealer or email Trek. They have been very responsive to my questions.

Clamp the seat mast... not the frame. If you do damage it you can replace the mast. I have a 2015 Emonda SLR and never had a problem with using my workstand.

Rdmonster69

The lines brake lines etc aren't clipped. That part was removed when the computer and light mounts were installed. I may see 8f they can be loosened some.

The seat mast is carbon as well although they said it wad OK to ckamp there.. the issue with that is then the bike is too low for me to easily work on it !

I didn't really plan on buying a tube but decided to grab a co2 inflator and levers to fill up the trick little bag in bae downtube. They only had short ish ones and stupid long..... I went stupid long, I would have asked a shop emplobut u had to rake a number for service...ain't nobody got time for that !!

HTupolev

Weight differences between road bikes tend to have a pretty subtle impact on overall performance, it's not surprising that the weight doesn't correlate to the performance difference.

In your photograph, there's something very weird going on with the fit on the old bike: the handlebars are rotated way up. This doesn't necessarily explain anything, but it doesn't fill me with confidence that the bike is actually set up very well for you. Weird fit quirks can definitely have big performance costs, both aerodynamically and in terms of rider power production.

What tires are those on the old bike? Tire choice can have a big impact on speed, and the R3s on your Domane are reasonably quick. If the tires on the old bike are very cheap, or if they're a durability-focused model, it could explain a good chunk of the difference.

It's also likely that your new bike has somewhat better aerodynamics.

biker128pedal

I carry a long stem tube in case some else with deep rims needs a tube. Oh I was able to fit a Park patch kit below the burrito roll in the frame.

Mojo31

I use the Silca Hirobel when putting our carbon bikes on a work stand: Silca Hirobel Frame Clamp | Backcountry.com

Rdmonster69

I tilted the bars up quite a bit on the old bike very recently. Maybe I went too far but it feels pretty good. It more closely matches the feel of the bars on the Domane. It is possible the pic exaggerates the tilted look. The hoods were not easy to use before and are cake easy now. It is also much easier on my neck in this position as I had some serious neck injuries/surgery in December. I wish I had changed it like this sooner. If anything the bar is narrow for me as it is an Easton carbon bar I bought on close out.

The old bike has Michelin power road on the front and power endurance on the rear, also newer and I like them quite alot. New bike is def more aero.

I think most likely the old bike needs the BB cleaned and repacked as it doesn't spin nice and free ...no real drag just doesn't whip around very long when free spinning it without the chain. Also the gearing is crappy so I imagine that makes a difference. I got the Dura Ace crank used and it's not a compact and the rear cog is set up for a triple. Its a work in progress lol. Plan on all that maintenance when it gets a little cooler. Right now it is in my car for a quick 25 miler if the rain holds off !!

Rdmonster69

Very cool ....might have to invest in one of those !!

msu2001la

Nice looking bike.

1. Speed difference is due to aerodynamics, tires, riding position and probably some of that "new bike" feeling.

2. The valve stem in your photo doesn't look too long to me, but you can try 60mm to see if it works better.

3. Riding no handed you probably just need to get used to your new bike. I have also experienced this feeling on new bikes and it usually goes away after a few rides.

4. Definitely don't use a clamp on any of the carbon frame tubing. Even "lightly clamping" can result in damage, as the clamp will still try to resist any twisting forces as you work on the bike. Carbon is strong, but not in this direction.

Rdmonster69

Those bars do look crazy upturned at that angle. The top of the bars are aero and in actuality they are tilted just slightly past horizontal. The brake hoods project out at a similar angle to the Domane so maybe I have them mounted a tad low and had to turn the handlebars up to compensate. The drops are not parallel to the ground but not intended to be with this type of bar as far as I can tell. A few more rides to test em out and if need to I can turn them down a little.