Will a Sugino triple crankset fit my Campagnolo-equipped bike?

[onlyhuman]

I've been thinking about providing my new oldish racer with some more forgiving gearing for hilly rides, and I've just realised I have a Sugino triple crankset I recently and rather luckily acquired. It is currently fitted to my (Shimano-equipped) Trek hybrid.

It's a Sugino Mighty 900, with a 42 tooth large wheel. The racer currently has a Campy 53 42 crankset fitted. Will the triple fit and work properly? Of course I can just try it and see, but I thought I'd ask first, in case it obviously won't work, or will cause some damage. I am not an expert.

 

[jimboalee]

I've been thinking about providing my new oldish racer with some more forgiving gearing for hilly rides, and I've just realised I have a Sugino triple crankset I recently and rather luckily acquired. It is currently fitted to my (Shimano-equipped) Trek hybrid.

It's a Sugino Mighty 900, with a 42 tooth large wheel. The racer currently has a Campy 53 42 crankset fitted. Will the triple fit and work properly? Of course I can just try it and see, but I thought I'd ask first, in case it obviously won't work, or will cause some damage. I am not an expert.

Putting a Sugino crankset on a Campag equiped bike will damage your reputation.

Or create you one.

 

[TheDoctor]

I doubt the front mech will work well, but aren't campag non-indexed at the front? An MTB front mech should fit and work nicely if so. If you're going to stick a Japanese chainset on there, may as well go for maximum outrage from the Campag tifosi

 

[onlyhuman]

Putting a Sugino crankset on a Campag equiped bike will damage your reputation.

Or create you one.

Hi Jimbo,

I noticed in another thread you mentioned that if one used a particular chainwheel/sprocket combination, any expert cyclist who saw this would know immediately that you didn't know what you are doing.

I was thinking about that during my weekend ride. I set out from home and rode for about 40 miles. During that time I saw maybe three other cyclists. Only one of these looked even remotely like an expert, in that he was wearing a jersey and a cycle cap, but then he had a plastic shopping bag swinging from his handlebars, which made me think perhaps he didn't really know what he was doing himself. In any case, he was on the other side of the road. I think this is probably typical of the level of cycling activity around here. I think it's quite likely that nobody but me would ever notice I had a Sugino crankset, and I don't think it is likely I will ever have a cycling-related "reputation" either good or bad, and I don't think I care much either way.

In short, I'm really only interested in the practical question whether the Sugino triple will fit and work. I'm wondering what the determining factors are. Will the spindles be the right shape and size? I have Ergo shifters.

 

[andrew_s]

If the BB was right for Campag, it will be an ISO taper, and the Sugino chainset will be a JIS taper.
One is very slightly larger than the other, so although it goes on OK, the crank goes either about 3-4mm further onto the spindle or or 3-4mm less far on (I can't remember which way round). It's a bit variable dure to the tolerances.

If the crank doesn't go on quite as far as normal onto the axle, it's generally OK if you make sure the crank bolt is properly tight.
If the crank goes too far onto the axle, you have to check that the crank bolt isn't just tightening down against the end of the axle. If it is, you'll wreck the crank by riding with it too loose. To check, fit the crank to normal tightness, then remove the bolt and check that the end of the axle is below the washer flats in the crank.

Either way round, you'll need to adjust the gears afterwards.
Front shifting will be relatively poor using a 42T large chainring with a mech designed for a 52T chainring.

 

[jimboalee]

I was given a Sugino chainset once. There was possibility of putting a 36 tooth ring on it with the 52 outer ring.

That would have made my Pug PX10 easier to ride up the hills, but wait....

A Peugeot PX10LE 531 racebike WITHOUT a Stronglight chainset, Mon dieu, zut alors, Sacre bleu..!!

I would rather struggle than let a foreign object contaminate the Pug.

 

[onlyhuman]

Either way round, you'll need to adjust the gears afterwards.
Front shifting will be relatively poor using a 42T large chainring with a mech designed for a 52T chainring.

Thanks very much Andrew. Can you tell me what sort of thing I would need to adjust? Is the amount of movement on indexing adjustable on a front derailleur? And I'm not disputing your statement that shifting will be poorer, but I'm interested to know the cause.

Bernie

 

[andrew_s]

The front mech should push the chain over as close to the chainrings as possible. If the mech touches the chain further out, it's got to push further to move the chain the same amount at the rings where the change happens.
If you use a 52T mech on a 42T ring, the curve of the outer plate is further away from the chainrings at the bottom end than it would be if it were a 44T mech with a more sharply curved outer plate.
It will be changes onto and off the granny that are worst, comparatively.

 

[onlyhuman]

Thanks very much Andrew, that's really clear.