Shimano's DH-3N72 dynamo hub - details for wheelbuilding

[Nonsteeler]

Rose sells the DH-3N72 dynamo hub for 27.5€ (there is more very interesting & cheap stuff in this section of website: Roseversand Shop MTB Rennrad Trekkingrad Versand Fahrrad)!

Anyway, I bought one and also a rim but I couldn't find any technical details (ie pitch circle diameter, flange distance, diameter of the spoke holes) of the DH-3N72. Does anyone here know those things? Thanks!

[MSeries]

Just measure it.

[border-rider]

Just measure it.

That's what I did.  Sorry, but I don't recall the answers.

[Nonsteeler]

Just measure it.

Just measure it.

That's what I did.  Sorry, but I don't recall the answers.

Sorry, I didn't make that clear. I don't have the hub yet and I want to order some spokes soon. But if I can't find the data then I will resort to my callipers as MSeries and Mal Volio suggested and everything will just take a bit longer...

[border-rider]

Ah, OK.

I'd offer to measure mine but it's the roller brake compatible version so it might not be the same.

I think I tried quite hard at the time to track down info on the hub dimensions, but I couldn't.

[redshift]

I think one of the online spoke calculators (DT Swiss?) has parameters for SON and Shimano hub dynamos in its list.  I remember seeing it when I was working out the spoke lengths for speedy, and thinking it would be useful for the next wheelbuild on the tourer.

[Nonsteeler]

I think one of the online spoke calculators (DT Swiss?) has parameters for SON and Shimano hub dynamos in its list.  I remember seeing it when I was working out the spoke lengths for speedy, and thinking it would be useful for the next wheelbuild on the tourer.

I know and you're kind of right: DT Swiss has two dynamo hubs from S (Inter-L - whatever that is - and HB NX70  - whatever that is ) but not exactly the one I bought. But maybe they're all the same...

[MSeries]

Try Googling for it. Someone somewhere is bound to have asked on a forum far far away.

[border-rider]

HB NX70 is the hub-brake compatible version of their old (and less efficient) dynohub.

Inter-L means it can be used as part of some sort of integrated lighting/electric gear change system, I think (but I'm not sure)

[Nonsteeler]

Try Googling for it. Someone somewhere is bound to have asked on a forum far far away.

Well, I did this and again you're right, someone asked that before and got no useful answer. See: Re: Wheelbuild parameters for DH-3N72 dynohub?. But maybe I searched with the wrong technique?

And just in case, yes, I tried shimano tec docs but again I couldn't find the information. But then, maybe I missed it...

HB NX70 is the hub-brake compatible version of their old (and less efficient) dynohub.
Inter-L means it can be used as part of some sort of integrated lighting/electric gear change system, I think (but I'm not sure)

Thanks for the info!

[Craig]

Isn't it identical in size to the DH-3N70 / DH-3N71 ?
Which might be easier to find details for. The DH-3N70 is listed in Spocalc.

[alexb]

Rose sells the DH-3N72 dynamo hub for 27.5€ (there is more very interesting & cheap stuff in this section of website: Roseversand Shop MTB Rennrad Trekkingrad Versand Fahrrad)!

Anyway, I bought one and also a rim but I couldn't find any technical details (ie pitch circle diameter, flange distance, diameter of the spoke holes) of the DH-3N72. Does anyone here know those things? Thanks!

I did the same thing, in fact what I actually did was ask them to do the maths and then send me alll the bits. It was cheaper than buying a set of spokes in the UK. Even if you have the rim and the hub, just e-mail them and ask. they are really helpful and will have the numbers to hand anyway.

[rogerzilla]

I can measure one if you're desperate.  I have two of them.

[mark]

         Edd, an easy to use spoke length calculator
      

HTH

[Lotum]

Isn't it identical in size to the DH-3N70 / DH-3N71 ?

It is not identical, at least according to what I've measured. The DH-3N71 is also heavier and more nicely finished than the DH-3N72.

DH-3N71:

Over Locknuts              99.4 mm   (nominally 100 mm)
Flange To Flange          56.0 mm   
Spoke Hole Circle Dia    74.0 mm   
Flange to fork LEFT       21.5 mm
Flange to fork RIGHT    21.8 mm


DH-3N72:

Over Locknuts              99.7 mm   (nominally 100 mm)
Flange To Flange          56.0 mm   
Spoke Hole Circle Dia    70 mm   
Flange to fork LEFT       21.9 mm   
Flange to fork RIGHT    21.6 mm   

I've successfully built two wheels with the DH-3N71 and one with the DH-3N72 using the dimensions above, so they're not very far off.

[rogerzilla]

         Edd, an easy to use spoke length calculator
      

HTH

I have had iffy results with that.  It seems to give different lengths to Spocalc.

[border-rider]

It gives very similar data for the DH-3N72 as Lotum posted though.  It's a useful resource for dimensions I suppose.

Maybe plug these into Spocalc.

Shimano Nexus DH-3N72 dynamo , front
Right flange ø: 70.0
Left flange ø: 70.0
Centre to right flange: 28.5
Centre to left flange: 28.5
Spoke hole ø: 2.6

[Nonsteeler]

Thanks for all your input, in particular for:

I can measure one if you're desperate.  I have two of them.

Thanks a lot for the offer. Luckyly I don't have to come back to it.

mark, I have never come across that tool. Nice and good starting point! Thanks!

Lotom, thanks for sharing your data.  Much appreciated!

I did the same thing, in fact what I actually did was ask them to do the maths and then send me alll the bits. It was cheaper than buying a set of spokes in the UK. Even if you have the rim and the hub, just e-mail them and ask. they are really helpful and will have the numbers to hand anyway.

True, kind of forgot that option because I was so sure the info must be out there ... it is such a common hub. And true, they are very helpful - also was in touch with them about another wheelbuilt.

[gordon taylor]

I've struggled to get dimensions for some Shimano hubs. It would be great if the company would just put them online somewhere... the little(r) people like Hope and Surly manage it. Come on Shimano, please?