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Sheldon Brown makes a point about different spindle lengths being to do with seat tube diameter, when listing Shimano BB sizes. He says, Shimano sometimes specs two different lengths for the same crankset. This usually relates to the diameter of the seat tube. The shorter dimension is normally preferred, but bikes with fat seat tubes may require ...


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We can make this easy... Lets assume your frame is totally straight and not bent in anyway. Measure front chainline. Chainline is the distance the chain is from the bike's centerline. You will need an inexpensive machinist's scale . A machinist scale is just a small 6" long ruler. On a machinist's scale the zero mark is exactly at the edge of the ...


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I went to take pictures of the BB installation as @Batman suggested. After removing the crank arm, I actually noticed an offset of 1-2 mm on the drive side, like @mattnz anticipated. However, I also noticed that there was a gap of about 1 mm between the frame and the BB lid: After this observation I googled a little bit, and learned from this forum thread ...


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The Alfine has a chinaline of 42.7mm for a single crank and the Ultegra 43.5mm for the double and 45mm for the triple. For the double the chainline is measured halfway between the 2 rings so the outer ring will be even further out, but the inner further in. Sheldon says "With typical 5 mm chainring spacing, this puts the inner at 41 mm, the outer at 46 ...


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There seems to be a bit of confusion in your question about how chainline is measured, and it's relationship to bottom bracket spindle length and the rest of the bike - you haven't given enough information to answer your question. The rear hub and sprocket's chainline measurement is required to decide how to adjust the chainline in the front. Even then, ...


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I would surely go by changing the bottom-bracket for a longer one (be it changing the spindle as you said, or installing a sealed Shimano-type one). If you don't want too much to keep your current bottom bracket with separate spindle and cups, the sealed one is much more reliable, long-lasting, play-free and water-resistant. To find out the correct size is ...


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Just did a conversion last week and ended up with a mash of Road, MTB and BMX parts. I did all the measurements but at the end of the day I had no assurance the chain line was straight so my advice is get hold of old parts or cheap parts and fit them and refine the spec of the parts visually. For example the two chain rings I used varied the chain line by ...


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As you have mentioned, the point of having a variety of spindle lengths is to allow selection of a BB which creates the proper chain line, while ensuring proper clearance from your frame. (Typically 51 mm from BB center to the center of the chain ring set. The assumption that using the Italian BB mandates a wider BB spindle is not correct. You should have ...


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Why would the spindle lengths be different at all? Why wouldn't the Italian BB spindle have the bearing shoulders further apart by 2 mm while keeping the 113 mm length? No idea about this. The great thing about bicycle standards, is there's so many to choose from. I would guess it's to keep the same amount of spindle sticking out of the bottom bracket ...


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Did this sound start when you took the biek to the LBS? What else did the LBS touch? See if you can take the chain guard off temporarily to see if the sound goes away. Your description also sounds a lot like a BB that the shop overtightened or under tightened. If you have a torque wrench you could investigate this yourself, otherwise I would take it back ...


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I've occasionally had this when the drive side axle was slipping in the drop out. When enough torque was applied to the pedals the axle moved just enough that the front of the tyre was rubbing on the inside of the left chain stay. You could check the paint there and see if there is any evidence of rubbing. If this is the problem, a chain tug would solve it. ...


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if you have a double chainring crankset, and are just running one ring, on the inside of the crank, you could try moving the chainring to the outside of the crank (where the big chainring would have been). Also - what is your chain tension like? The noises could also be attributed to a very tight, very cheap KMC chain. you should have about 1/4" "sag" or ...


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Your other option is to move the chainring. I don't know what your cranks look like, so it may not be practical, but maybe you can add some spacers underneath the chainring mounting bolts. This may also require longer bolts.



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