39/52 possible with gears?

[CdM123]

Hi All. I’m riding the Ultegra 6800 11spd. Will a 39 chainring work if I use it with a 52 chainring in terms of shifting from the one to the other?

[Knersboy]

Most definitely, back in the day the most common cranksets were either 39/52 or 42/52.

[Thomo]

No problem.

Issues start when increasing the size difference between large and small chainrings.

And even that sometimes works just fine.

[Darryllk]

This is what I've been looking at doing as well for some time, swop my current 36 out with 39

Just need to find a cheap option & one compatible with ultegra R8000 crankset 

[TNT1]

The only difficulty will be finding a 52. Most common is a 53 these days, I'd assume most places only have stock of 53's.

[eddy]

39/53 was the standard for many years. All my 10spd Campag groupsets have that.

 

ps.

 

One bike has a "Climbing" cluster on. 11-25

[Jewbacca]

The only difficulty will be finding a 52. Most common is a 53 these days, I'd assume most places only have stock of 53's.

Now days the semi compact cranksets are 52/36, so it is probably not too difficult. I'm assuming the OP has a 52/36 and wants to swap the 36 with a traditional 39 granny.

 

Definitely.

 

I am not sure what BCD those semi compact cranks are but I would assume 110bcd. I have seen some traditional size 110bcd chanrings for sure. It's not 'common stock' but you can definitely get them

[Schnavel]

The only difficulty will be finding a 52. Most common is a 53 these days, I'd assume most places only have stock of 53's.

 

You would be surprised - the majority of bikes now come with the 52/36 semi-compact cranksets.

[JacBrand]

Yes it is. As stated above, back in the days 39/53 was the norm. At one stage I rode 42/52...

[DieselnDust]

Hi All. I’m riding the Ultegra 6800 11spd. Will a 39 chainring work if I use it with a 52 chainring in terms of shifting from the one to the other?

 

 

It should not be a problem. However.....

 

The Shimano Chainrings are designed to work in the following combinations:

53-39 (MD)

52-38/52-36 (MB)

50-34 (MA)

These are designed to work with a combination of like type i.e. 34T MA + 50T MA and you cannot combine a MA with a MB or MB with MA or MD.

 

So in your cse you would  need to combine a 39T MD with a 52T MC big chainring.

This combination will deliver the best front shifting. If you use the 52T MB the ramp on the back end of the chainring will not align with the teeth on 39T chainring which can result in dropped chains

 

Models:

34 tooth:

- Type: MA

- Manufacturer Part Number: Y-1N234000

 

36 tooth:

- Type: MB

- Manufacturer Part Number: Y-1N236000

 

38 tooth:

- Type: MC

- Manufacturer Part Number: Y-1N238000

 

39 tooth:

- Type: MD

- Manufacturer Part Number: Y-1N239000

 

42 tooth:

- Type: ME

- Manufacturer Part Number: Y-1N242000

 

50 tooth:

- Type: MA

- Manufacturer Part Number: Y-1N298080

 

52 tooth:

- Type: MB/MC

- Manufacturer Part Number: Y-1N298110

 

52 tooth (x38):

- Type: MC

- Manufacturer Part Number: Y-1N298120

 

53 tooth:

- Type: MD

- Manufacturer Part Number: Y-1N298090

 

54 tooth:

- Type: ME

- Manufacturer Part Number: Y-1N298130

 

55 tooth:

- Type: ME

- Manufacturer Part Number: Y-1N298140

 

Note to Type Designation:

The type designations (with one or two letters) indicate that the chainrings can be combined with each other. Since the large rings have specially shaped teeth and shifting aids that make it easier for the chain to climb, full shifting performance is only guaranteed with matching small rings - and vice versa. A chainring of type XY should therefore only be ridden with a chainring of type XY. The same applies to all other types.

Edited October 13, 2020 by DieselnDust

[NotSoBigBen]

Just wondering why would you want to do that?

[DieselnDust]

Just wondering why would you want to do that?

 

 

Especially when a 52-38 is a designed combination under MC type chainrings

[Darryllk]

Isnt the 38t harder to source in RSA versus 39t?

 

Or let me rather ask, where can one get a 38t locally?

[DieselnDust]

Isnt the 38t harder to source in RSA versus 39t?

 

Or let me rather ask, where can one get a 38t locally?

 

 

They're all fairly simple to source as the distributor brings in all the combos.

The 38T might be more rare since the folliwng combo's are most popular

53/39

52/36

50/34

 

I use a 52/38 and have been for a long time as the 52 MC chainring is a whopping R1000 cheaper than the 52 MB/MC which can work with either a 36T to 38T chainring.

I've never had a problem replacing the 38T chainring. They've always had stock pre Covid.

[Long Wheel Base]

This thread is becoming seriously Higher Grade. Why do they(the OEM) make things so difficult?

We should be able to put what ever size we want on there. Sure when the jump is big you will struggle to change compared to standard but it still works. I am running a 44/56 on the race tandem and prior to the 44 I had a 42 and it was not easy changing, especially up but the 44 made it easier but I struggled to get a 44. Eventually imported it from some french track cycling website, then had to stick the chainring on the lathe and make it a bit narrower as it was flipping thick.

[TNT1]

You would be surprised - the majority of bikes now come with the 52/36 semi-compact cranksets.

Pffftttt!

39/53 and 11/21 for me thanks. 

 

I do feel old though I just changed my training wheel's cassette to a 12/25...