Questions re: Chainrub on compact Q ring

[NiFTY]

So I have a 54cm EVO with SISL2 cranks with 109mm spindle and 52/36 Q rings with an 11/28 on the back (both set in OCP3). SRAM 10 speed.
Crank is set up as per standard SISL2 instructions re: spacers

When running in the little ring I start hitting the inside of the big ring on the 4th smallest sprocket.
Normally I don't ride in the little ring much but up certain steep climbs, particularly when sprinting for the line I find myself in some of these crossed gears. This can obviously be quite alarming when the chain grabs the shift pins and tries to derail itself to the big ring mid sprint.

Besides the obvious - shift to the big ring comment - which is difficult to accomplish on an 8% grade climb, are there any other ideas? I don't want to mess up shifting at the front or bugger the chainline, but has anyone tried with success adding small spacers between the chainrings (0.5mm) or would this result in the chain lodging between the rings?

Other options are spacing the DS further outboard or trying an 11 speed chain.

I am at the hands of your collective wisdom.

[eric]

I added .6mm chainring spacers on a Lightning crank with Sram rings, between the big ring and the crank. .6mm is the smallest I could find. They are in the QBP catalog so you can get them from any LBS who are willing to order them, and some on line stores. It helped the rub in the small ring and smaller cogs and I didn't have any shifting problems. There are no standards for the thickness of chainring arms or the offset of the chainrings. So some combinations end up with the chainrings too close together. You'll have to try it and see if it causes a shifting problem for you.

Make sure the chainring bolts have enough thread engaged.

11sp chains have thinner side plates, so the rear shifting would be affected if you're using 10sp.

Getting the spacers on is a biut fiddly.

[Omiar]

I have the same issue, although I have every part different besides the Q-rings. It wouln't call being on small chainring and on 3rd or 4th sprocket cross chaining.
Not really much you can do, because it is just a very poor/old product design. The shorter the chainstays, the sooner/more it rubs.

[mrd]

This has been done effectively by a friend using 52/36 Q rings and a similar cassette on an S-Works Tarmac disc. ( 11 speed Di2 9070)Grind a small amount off the inside of the 52 ring where it is catching, both on the pins and to the body of the ring. I would do it all the way round. He can now use all but the smallest two cogs (11/12 for you). i would do it with hand file and a dremel on the pins. His Di2 shifting between front rings is unaffected. The work was done by a Concept Store.

My tip to him was to deliberately ride with the chain catching for a few miles but not under load, so in your case probably 36X13 or so that the inside of the 52 ring gets "scratched". You then know where to focus your efforts. It will not catch on the low points of the Q ring so you don't actually need to file all the way around the ring.

mrd.

[NiFTY]

Okay - so I spaced the big ring outboard with a 0.5mm washer under the big ring and re-adjusted the FD. I can now get to the 2nd smallest sprocket before I get the sound of scraping and it doesn't try and ramp until the 11T - a combo I would never use anyway. Success.