SpedFast

I'm not here to ask a question just to post some info in case someone else is considering upgrading from an 11-28 cassette to an 11-32 cassette. Them hills are getting steeper every year and now that I'm mid-70's I need taller gears to reach the top. Or at least I will next year. While this setup actually works, despite Shimano's claim otherwise, I will admit that shifting performance is slightly effected and it took me a bit of time to smooth it out. I should also add that it's not my intention to cross chain, I just don't want to screw something up if it happens and this works!

Small to Small gears 36T front-11T rear

36T-11T small to small

52T front-32T rear Large to Large

Large to Large 52T-11T

Info as follows: 2016 Fuji 2.0 Alloy frame/carbon fork It was Fuji's inexpensive race bike at the time.
This is a Shimano 11 speed 105 group 5800 with a Shimano 105 SS (short cage derailleur).
Chain length is same for 11-28 and 11-32 cassettes-no change there.
The "B" screw adjustment is critical to optimum shifting performance.
For some reason, I had to readjust my limiting screws slightly also, but not sure why that changed.
I'm also attaching pics to show that the chain length for both cassettes is fine and that it works.
Please ignore the background junk and especially that rusty kickstand mount.

Iride01 

I'm impressed. Mostly that you provided the pictures that pretty much fully back up your narrative and show that there isn't a slack chain hanging when in the small/small.

What's the distance between the center of the axle and the center of the mounting bolt for the RD? My son's bike with a 105 and a RD-5800-GS has the spacing between about 1.15 inches or about 29.3 mm measured with digital calipers.

I'm just wondering if your bike has more distance between. Which might explain why it works for you and may not work for others. Of course then it might be that some bikes come with even less spacing than we have from the axle to the RD mount.

That's why I feel Shimano is so conservative with their numbers. Because they are trying to account for the one person with the oddball bike that it wouldn't work on.

FBinNY 

The photo shows a relayltively short hanger typical of road bikes, so I doubt that's a factor.

Shimano is conservative in their specs because mechanic skill becomes more important at the fringes. So it's not a question of working or not working, but managing the grey zone.

Iride01 

I thought the hangar looked pretty short too. But with the trainer mounted and in the way I wasn't sure. I am just somewhat surprised that it clears that 32 tooth sprocket and is able turn without the jockey wheel getting too familiar with the sprocket. The 28 tooth to the 32 tooth is about 0.35 inch difference in radius and that much more of a jump for the RD.

But it has been seen in other threads that many others have gotten away with the same. So maybe a lot of the other people buying Wolf tooth hangers for just that move to a 32 max low sprocket are just wasting their money. At least if they didn't try without first.

Kontact

What does it look like when you are in the 32x36 combo? That's usually the problem - the pulley is up against the 32 sprocket.

SpedFast

I'm going to take that as a compliment haha. Thanks It means a lot coming from you as I know your knowledge far exceeds mine.

SpedFast

I will get that measurement for you later.

SpedFast

I'll get that picture and post it later.

Kai Winters

Wow, it looks like you are right at the limit of how much you can push the drivetrain before it doesn't work anymore...or works poorly.
Likely the shifting problem you are noticing is due to the amount of force on the rear derailleur based on the gear you are in and the load on the return spring in the rear derailleur.
Based on the picture of the little/little...36/32...adding a link to the chain may be a bit too long and a too loose chain...though in reality how often does anyone use this gear combo so the likely hood of a problem is close to zero.
Based on the picture of the big/big and the position of the pulley cage whilst in this gear combo I'd want to add another link or two and see how it affects the shifting quality. I'd bet it would be a lot better because you'd be reducing the load on that return spring.
You are likely at the limits...hehehe...of the limit screw as well but I've used longer limit screws in the past and they generally work...but sometimes it is a bit of a compromise and you have to think about the direction of compromise. Again how often are you in the big/big??? Depending on what's going on it may happen more often than one thinks. I don't hesitate to cross gear if I'm in a race or racing with friends and it is faster to shift into a cross gear than to fiddle with shifting the chain rings then the rear gears to achieve the proper gear. I don't give it a thought and cross gear away until I'm able to shift into a more efficient and less wearing gear ratio.
Experiment, compromise based on your riding needs and do what seems best...you can always change it back if you don't like it.

tFUnK

Good stuff. I was able to get 32t big cog on a Shimano short cage before as well.

The total chain wrap part was aided by the fact that I ran 46/34 up front. Not sure if I could have gone 50/34.

SpedFast

When going to this size cassette, the "B" screw adjustment really comes into play. I took it for a 20+ mile ride today and did a few minor tweeks on the barrel adjuster and frankly, I can't tell any difference in the shifting from the 11-28 cassette. I just had to work the wax off the chain. It goes smoothly from big to small cogs in both the 36T and the 52T chainrings. I'm quite chuffed. I was ready to spend the money for a medium cage DR if this didn't work, but it does

36T front-32T rear

SpedFast

Hey Kai, I got the shifting smoothed out after taking it for a 20+ mile ride and doing some more tweeking on the barrel adjuster. It seems I had to knock the fresh wax off the chain and then all was good. But your comments all make sense. I don't plan to cross chain, no one ever does, but it happens and I really just wanted to be sure that I didn't bust my DR or put it in the spokes or something equally bad. Smokey

SpedFast

There's an individual on Utube that claims a 50-34 actually works better than my 52-36 but a 53-39 won't work without a longer cage, just in case you're thinking about that upgrade in the future.

SpedFast

It's very close to what you came up with.. I used my digital calipers also and came up with 29.4 mm, but even out of the trainer it's hard to get 100% accuracy because the 2 points are on different planes and I ended up eyeballing it somewhat. HTH (Axle ctr to DR pivot ctr)

Kontact

That's absurd. The rear derailleur has no idea what rings you're using, the first two are both 16t splits and the last only 14t. Of course the 53-39 works. It just might need an extra link longer chain.


Glad your set up worked!

SpedFast

Maybe I misunderstood him and he was referring to needing a longer chain, not cage. What you're saying makes more sense.

Kontact

There's also a lot of absurd on youtube.

SpedFast

Update: I've put almost 300 miles on the new 32T cassette and everything is working fine. I take the hills slower now, but so much easier than that 28T and I didn't have to give up any of my higher gearing by going to smaller front chainrings. I know I would miss my 52-11 overdrive.