Road Cycling
- Thread starter FrenchTart
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Please - need some help from the technicians amongst us:
Ultegra 6800. When the front derailleur is in small front ring, the RD goes all the way up and down the cassette perfectly, no problems at all. However, when changing to BIG front ring, the RD hesitates slightly going from the very largest rear cog for 3 changes down the cassette (moving from large cogs to small cogs) then suddenly the hesitation is gone after 3 changes and it'll then go all the way down to the very smallest cog no worries whatsoever.
I could understand if there was hesitation on the RD when in the front small AND the front big rings - but for the RD only to hesitate when the chain is on the big ring at the front has me completely bamboozled.
I'm absolutely positive the indexing is spot on.
I'm positive everything is clean of gunk.
I don't think my chain is worn - it's only done 1700/1800 miles.
Ideas?!
@Jonny ///M maybe?!
Ultegra 6800. When the front derailleur is in small front ring, the RD goes all the way up and down the cassette perfectly, no problems at all. However, when changing to BIG front ring, the RD hesitates slightly going from the very largest rear cog for 3 changes down the cassette (moving from large cogs to small cogs) then suddenly the hesitation is gone after 3 changes and it'll then go all the way down to the very smallest cog no worries whatsoever.
I could understand if there was hesitation on the RD when in the front small AND the front big rings - but for the RD only to hesitate when the chain is on the big ring at the front has me completely bamboozled.
I'm absolutely positive the indexing is spot on.
I'm positive everything is clean of gunk.
I don't think my chain is worn - it's only done 1700/1800 miles.
Ideas?!
@Jonny ///M maybe?!
It's consistent behaviour, it's not inconsistent. Exactly what I'd have thought on the cleaning or indexing - but in the small front ring everything is absolutely perfect - all changes are perfect, it's just on the big front ring the rear changes are hesitant, but only for 3 changes, then everything is spot on after 3 changes. It's doing my head in.
Soldato
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- 23 Nov 2004
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I'd go with a hanger being inwards slightly assuming you've never touched the b screw.
Try putting an allen key in the mech bolt, pull it up vertically ever so slightly and shift. If it drops smooth then you'll need to actually bend it properly.
Whilst in the big ring and 4th cog up the block will give you a pretty straight chain line so have a look from the rear to see if it looks bent too.
Jockey wheels can often cause issues like this but I think this is a new mech?
Try putting an allen key in the mech bolt, pull it up vertically ever so slightly and shift. If it drops smooth then you'll need to actually bend it properly.
Whilst in the big ring and 4th cog up the block will give you a pretty straight chain line so have a look from the rear to see if it looks bent too.
Jockey wheels can often cause issues like this but I think this is a new mech?
Wow that one hurt. My first ride in the Zwift WTRL race series. Check that avg HR 
Other thought would be the guide cog being too close to the cassette, so the chainline is harder for the RD to move over, it's 'snagging' on the cassette when the chain tension is higher (when in large ring) but when tension is lower (little ring) it's able to move easier?
Can't think for the real/official names for it, but you'll find info on the screw to adjust that difference (how close the guide wheel is to the cassette) and how to measure if you look for info on changing cassettes with differing teeths.
Just a thought... If you've changed cassette size it might be that, or if the RD is junked up a little so isn't moving as freely, so is adding more tension, etc etc
I'd heard and seen this on a YouTube video about building a while ago but didn't realise it was so quick! Really thought it was more of a manual process to get things really accurate. Do you guys do much stuff through the mail? I've got an old deep rim & 10-speed hub it would be good to get built to just flog on. I'm not going to use it and couldn't seem to sell it as it is (bought from a clubmate with multiple broken & damaged spokes as a project I never followed through).
How good are the vouchers? I've a set of old arm warmers with a split on them, would be good to replace for minimum costs!
Could be chain, well worth checking it just to confirm!
Other thought would be the guide cog being too close to the cassette, so the chainline is harder for the RD to move over, it's 'snagging' on the cassette when the chain tension is higher (when in large ring) but when tension is lower (little ring) it's able to move easier?
Can't think for the real/official names for it, but you'll find info on the screw to adjust that difference (how close the guide wheel is to the cassette) and how to measure if you look for info on changing cassettes with differing teeths.
Just a thought... If you've changed cassette size it might be that, or if the RD is junked up a little so isn't moving as freely, so is adding more tension, etc etc
Yes it does look a little far, that's in big chainring looking at the arm & slack (looks ok)?
How is it at the other end of the cassette? If you still have a large gap then close it up a bit and test it. Think its the screw on the 'top' of the RD, near the hanger, not the H+L on the back.
I don't know what the correct distance/procedure is, but move it around a bit and see if it makes things better/worse. Certainly easier than bending the hanger which is really scary!
How is it at the other end of the cassette? If you still have a large gap then close it up a bit and test it. Think its the screw on the 'top' of the RD, near the hanger, not the H+L on the back.
I don't know what the correct distance/procedure is, but move it around a bit and see if it makes things better/worse. Certainly easier than bending the hanger which is really scary!
Soldato
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You don't check and adjust the B Screw tension in that gear, the main thing that changes that angle are chain length and how tight a loop is on the rear derailleur cable loop. B Screw adjustment is done in the lowest gear.
Giant TCR is really short so the spring of it holds the mech further away from the cogs slightly.
I'd say if you back of the tension a quarter to half a turn and it helps it drop but then the problem is moved to the downshift i.e you click and it doesn't jump up then you have a bent hanger.
Giant TCR is really short so the spring of it holds the mech further away from the cogs slightly.
I'd say if you back of the tension a quarter to half a turn and it helps it drop but then the problem is moved to the downshift i.e you click and it doesn't jump up then you have a bent hanger.
Jonny, he's not adjusting in that gear, just trying to show/see why it seems to happen around that gear. 
Got the Castelli ROS cap as a bit of a test as it was a deal (£20). Neat idea, but only really suited to spring/autumn. It's not a thick enough material to provide warmth and only a little wind protection, but is 'boil in the bag' enough not to wear in summer even with the front open. Some shower protection but not from real british rain. It's good this kinda weather when it's not cold but you need 'something' with a little protection.
A general cotton cap is similar but gets wet, this one provides a little more protection and although 'clammy' feels like it dries out. It's comparable to the Sportful NoRain hat, but tighter fit and less rain protection (that one keeps more moisture off). They're both overpriced at £30 but at £20 (what I got the ROS for) they are both ok purchases when you want more from a cap.
Annoying orange colour doesn't match any of my kit, but the grey one wasn't on special...
Got the Castelli ROS cap as a bit of a test as it was a deal (£20). Neat idea, but only really suited to spring/autumn. It's not a thick enough material to provide warmth and only a little wind protection, but is 'boil in the bag' enough not to wear in summer even with the front open. Some shower protection but not from real british rain. It's good this kinda weather when it's not cold but you need 'something' with a little protection.
A general cotton cap is similar but gets wet, this one provides a little more protection and although 'clammy' feels like it dries out. It's comparable to the Sportful NoRain hat, but tighter fit and less rain protection (that one keeps more moisture off). They're both overpriced at £30 but at £20 (what I got the ROS for) they are both ok purchases when you want more from a cap.
Annoying orange colour doesn't match any of my kit, but the grey one wasn't on special...
Soldato
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- 23 Nov 2004
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Sorry @Roady was skim reading whilst working away and drinking coffee.
I've ordered a Arione R5 from Wiggle as the R5 manganese was £35 which seemed pretty good so cheers for the offer of yours.
My mtb for just eat is comfier than my road bike, maybe I'm just a pussy now but we'll see.
I've ordered a Arione R5 from Wiggle as the R5 manganese was £35 which seemed pretty good so cheers for the offer of yours.
My mtb for just eat is comfier than my road bike, maybe I'm just a pussy now but we'll see.
Argh I'd got them out but then with everything else moving around I hadn't taken you any pictures. Sorry, should've reminded me! That's a great price for one anyway.
I'm tempted by the KICKR offers as an upgrade over my Kinetic dumb trainer but then I had a thought...
If I got a power meter, I could use "proper" power instead of virtual on the TT but I'd also be able to use it on the road. Pretty easier decision to go for pedal based as I could put them on the Synapse in the summer, then come the winter move them to the Planet-X on the turbo. A crank based meter would mean faffing around with BB standards on the Synapse, whilst a hub meter would also suffer on the portability / compatibility side.
The single sided Vector 3s are ~£385 with double sided Assioma and Vectors £699. As I have an antique Edge 800, I know I won't get some features like Cycling Dynamics but the essential bits should be there.
Has anyone had single sided power pedals before? They are obviously a fair wedge of cash cheaper but is it inevitable you end up upgrading to a dual sided setup later?
I know Garmin have had quality issues with the Vector 3s, so I'm not buying them from eBay or Europe in case they need to go back!
If I got a power meter, I could use "proper" power instead of virtual on the TT but I'd also be able to use it on the road. Pretty easier decision to go for pedal based as I could put them on the Synapse in the summer, then come the winter move them to the Planet-X on the turbo. A crank based meter would mean faffing around with BB standards on the Synapse, whilst a hub meter would also suffer on the portability / compatibility side.
The single sided Vector 3s are ~£385 with double sided Assioma and Vectors £699. As I have an antique Edge 800, I know I won't get some features like Cycling Dynamics but the essential bits should be there.
Has anyone had single sided power pedals before? They are obviously a fair wedge of cash cheaper but is it inevitable you end up upgrading to a dual sided setup later?
I know Garmin have had quality issues with the Vector 3s, so I'm not buying them from eBay or Europe in case they need to go back!
