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I had an 11sp GX set up on my old hardtail.
I have a new frame which is boost and have ported the kit over.
Few issues:
I have converted the rear hope Hub from QR to boost - easy.
Now I only have 2 problems:
1. Chainring rubs in the chain stay - will a boost crankset fix this? Have tried putting a spacer in the current gxp set up but results in loose cranks.
2. Can't stay in the top cog in the back. I have played around with the limit screw and b tension to get it to say in while in the bike stand. Soon as I start riding it pulls down into the lower cog. Feels like the top cog is too far away from the mech now. There is a sizable gap between the hanger and the cogs now.
Do I just need to upgrade to a boost group set and buy a boost rear wheel?
Next time I will just buy a new bike.
How have you boost converted the wheel? Does it use an axle spacer/longer end cap on the drive side? If so the cassette is no longer in the correct place. For a hope rear hub the best kits are the wolftooth boostinator or fun works that put all the spacers on the brake side. This puts the cassette in the right place but does need a redish.
A smaller chain ring would sort the chain rub. If you've gone up a wheel size you might want this anyway.
Yes I have used hope boost kit.
Will try putting a spacer behind the cassette to get it in a better position.
Agree on the smaller chain ring.
Sound like the chain line will be terrible unless I upgrade to boost anyway.
Just a boost chainring will give you the chainstay clearance. Sram do the boost or not-boost in the chainrings, not cranks.
This will help with the chainline too. Then the b-gap for sram 11speed is....er dunno. More than shimano 11speed and less than eagle...
Boost via adaptors is a bodge, adding 3mm to both sides shifts the cassette inboard from the ideal position.
I have had mixed success with 10 and 11 speed shimano set ups
1) 10 speed with cassettes up to 42T worked OK with existing mech and minimum faff.
2) 10 speed with cassettes up to 46T didn't want to play ball as the cable clamp on the mech would foul the cassette, a hanger extender stopped that but the shifting wasn't great. Shortly after I killed the hub on that bike so went boost.
3) 11 speed with cassettes up to 48T would not work until i swapped the link and spacer round in the mech which moved it inboard by a few mm at which point it worked perfectly. No idea if you can do this with SRAM, you can't with all Shimano mechs.
Even if you get the mech working OK, you need to sort the cranks, boost cranks will move the chainring out. The cassette is sitting further in board than it should be. The chainline won't be ideal, it might work vaguelly acceptably or it might not. Hard to know.
Sorry, yeah it will be a bit worse. But a boost chainring or smaller non-boost chainring will be needed anyway as the current one hasn't got chainstay clearance.
It'll be worse and will make the large cog issue worse.
Boost by adaptor doesn't have to be a bodge if you use kits that do it 'properly', i.e. adding all the spacers (in the form of proper end caps) to the brake side and redishing. These kits do tend to cost a bit more though.
Hopes front kit is fine as the longer cap goes on the right meaning no disc spacer required. Their rear kit is crap compared to a wolftooth kit.
The only thing your cassette really cares about is the location of the chainring. Mechs have enough adjustment to deal with boost spacers etc, or at least, every mech I've ever used has way more than it needs going back as far as 8 speed. Going with all legit boost parts avoids problems and is simplest, but from where you are you're just one step away from it all working so don't get distracted or think you need a wheel or whatever, just cranks will do it. Or, some cranks have offset ring options, frinstance one of my direct mount cranks had an offset ring as standard so flipping it over moved the chainline loads.
People get a bit fixated on chainline, centreish is fine, it doesn't have to be perfect- there's actually a pretty good argument for having it offset a little "inwards" because that gets you better alignment in the lower gears where you spent more time and apply more torque but as long as it's pretty much in the middle, it'll be fine. It can be helpful to think of a double chainset, that's pretty much the range you want to be in.
(both my main frames are completely made out of non-boost bits, there's no downside. You don't get the "benefits" of a boost wheel but since they don't really exist that's fine)
I did the same with shimano 11speed and the wrong way (+3mm end caps on both sides) + boost sram chainring and it worked. Chainline is worse, but no issues with the chain falling off. 6mm b-gap though so less than a sram mech. Maybe luck that it worked because a spacer on the brake side and a re-dish would be better.
@northwind in this case I think you may be wrong. Yes a crank will solve the clearance issue but it will also make the big cog issue worse. If that won't work with the current crank it sure as hell won't with the chainring further out.
Front ring is 32T x sync. Sram X-Sync Steel 32 T 948CD... https://www.amazon.co.uk/dp/B013L37IDO?ref=ppx_pop_mob_ap_share
Ok understand about the chain line now thanks. Feels like the whole thing is going to bodge. Key is to shift the cassette nearer the frame.
Need to consider the week dish too.
Think I need to go 12speed ££££££