volosong

I asked in the mechanics sub-forum, but I know my "brothers and sisters" here a lot better and trust your views/thoughts/opinions.

My new build is coming along fine. Not really rushing it and have just a few more parts to get, (saddle, saddle bag, and pump). Being a non-braze-on frame, I ordered a banded FD with the groupo. Then, as I was pre-fitting the components, (really just day-dreaming about the final build), I realized that I would need another band for the chain catcher. Uugh. That's going to look elegant. Ummh...no! Since all these new carbon frames have a seat post that flares out the closer it gets to the bottom bracket, I can't mount a dog fang. So, I have a new braze-on FD coming from Competitive Cyclist along with a separate band. Then I can mount both the chain catcher and the FD to the same band. (Ah...that looks a lot cleaner.)

Anyway, my new wheels are sitting at the local FedEx office ready for me to pick up later today. What I would like to know is...

Can I safely run with 28mm tires on an Ultegra wheelset, (WH-6800)?

In the past, with my current WH-6700 and WH-7900 wheelsets, I've run both 23mm tires and currently 25mm tires. The new frame can handle 28mm, and with all the chip sealing around here, I think I'd like to try the bigger tires.

Thanks.

CACycling

Shimano says 23 - 28.

volosong

Where did you find this info? It's not in the product spec sheets. Can you provide a URL?

Oooh, wait! The WH-6700 sheet is still up on the screen and it says that the "Applicable tire size" is "Clincher tire / Tubeless tires" and "700c (19C-25C)". (WH-6800 tech docs not released yet on their web sites, and they don't include them with their products anymore, only a silly "user guide".) Then again, the WH-6700 spec sheet also says "Largest sprocket" as being "21-28T", but I'm running a CS-6700 with a 30T sprocket. (Looks like Shimano doesn't update their tech docs after the initial release of the product.)

Oh, thanks for the help.

NVanHiker

From "Dealers Manual" on Shimano Website:


The recommended tire sizes for installation to each wheel are as follows.
Series Model No. Tire size
DURA-ACE
WH-9000-C24-CL 23c-28c
WH-9000-C24-TL 23c-28c
WH-9000-C24-TU 20mm-25mm
WH-9000-C35-CL 23c-28c
WH-9000-C35-TU 20mm-25mm
WH-9000-C50-CL 23c-28c
WH-9000-C50-TU 23mm-25mm
WH-9000-C75-TU 23mm-25mm
ULTEGRA WH-6800-TL 23c-28c
Non-series
WH-RS81-C24-CL
WH-RS81-C35-CL 23c-28c
WH-RS81-C50-CL
WH-RS61-TL
20c-25c
WH-RS31-CL
WH-RS21-CL
WH-RS11-CL
„
.List of tools to be used
The following tools are needed to assemble this product.
Usage location Tool
Cassette sprocket
TL-LR10/15, TL-SR23
Adjustable wrench
Front hub
Freehub
Allen key 4mm, 5mm, 10mm, 14mm
TL-HS37 / 22
Pliers



I run 28's on wheels that will accommodate tires as narrow as 19mm. Aesthetically, 28's look a little oversized on road rims to me, but I've been touring for years on this combination and they seat securely. You'll be pleasantly surprised how you no longer worry about seams and pavement breaks, and how well they perform even off-road. 28's also seem to be a bit more rugged than their narrower cousins - i.e. fewer flats.

volosong

Cool. Can consumers get access to the "Dealers Manual"?

CACycling

I just Googled the model number and this came up:

https://www.google.com/url?sa=t&rct=j...ZfDXuSfO85ncvw

Tire sizing is on page 7.

BlazingPedals

Sheldon Brown's sizing chart at the bottom of this page, seems to allow almost any narrow rim to run a 28. In fact, below the chart is the disclaimer, "Note: This chart may err a bit on the side of caution. Many cyclists exceed the recommended widths with no problem."

volosong

@ CACyling. Well, duh. Guess I should look more closely to the search results. Thanks. File saved for future reference.

volosong

Update:

Went to my local Trek dealer and picked up a set of Bontrager AW1 Hard-Case Lite tires in size 700 x 28c and had the shop install them on the rims. The night before, I had decided to use a spare set of Continental Ultra Gatorskin tires in size 25c that I purchased a couple months ago as a backup for when needed on my other bike. But, I just couldn't get them onto the rim. That last nine inches just wouldn't go on. Saturday mornings, I decided to do an internet search and watched a couple of YouTube videos about how to get a stubborn wire-beaded tire on a rim. Nope. Won't go. Dang!

After deciding that it wasn't really right to go into a LBS and ask them to mount tires I purchased elsewhere onto rims I got off eBay, I opted to get new tires and tubes, and just have the shop mount them. Since Bontrager Race Lite Hard-Case tires are not available anymore, I looked at the Bontrager web site to see what the replacement was. (Would have gotten Continental Ultra Gatorskin also, but nobody locally carries them in 28c). There are only three Bontrager Hard-Case tires of the size I wanted, (AW2 Hard-Case Lite, AW1 Hard-Case Lite, and AW1 Hard Case). The shop only had the least expensive version in stock, the AW1 Hard-Case Lite. I got a third for the rear since they wear out faster than the front.

Tires fit fine on the rim and also into the frame. I haven't ridden on them yet because I'm still building up the frame. Maybe next weekend.

Thanks everyone for your help.