Disc brake to 130mm BCD adaptors are done

[recumpence]

Hey Guys,

We made 10 of these ISO disc brake to 130mm BCD sprocket adaptors today. These were designed out of necessity for my KMX [production] E-trikes. However, they will work for pretty much any disc to sprocket applications.

I went with 130mm BCD for two reasons;

#1 I wanted a higher tooth count than available for 110mm BCD. I wanted 50 plus tooth rear sprocket to be able to run single stage drive unit with correct ratio. This saves the customer money over having to run a two stage drive.

#2 Johnrobholmes is making a 110mm BCD adaptor. I did not want to step on his toes. So, it is good to have multiple options anyway.

The adaptor is offset exactly 1/2 inch (12mm) inward from the plane of the disc brake flange. This gives a proper chainline for most applications.

They are all CNC machined from 6061 billet and are tough as nails. The minimum wall thickness is 4mm. They are designed for absolute rigidity.

These adaptors are $49 (for those who may want one).

Anyway, I want to thank Miles for his help. I owe you one, Man!

Matt

Oh, keep your eyes peeled, I am machining lots of new parts right now. They will be shown very soon. :wink:

 

[johnrobholmes]

Ill take one. Two machinists flaked out on me in a row. Whats up with em? :lol:

 

[recumpence]

I'll trade ya. I need more stuff from you. I may need 4 more HV110s.

I will get in touch with you.

Oh, I grabbed a 65 tooth belt from the shop. I can ship that out with your sprocket adaptor.

Matt

 

[regmeister]

deleted

 

[gogo]

Is it possible to use a disc brake with this?

 

[recumpence]

Is it possible to use a disc brake with this?

The face of the adaptor where the disc would normally go is 4mm thick. So, if you wanted to try running a disc, the disc would be offset 4mm toward the dropout. Also, there would be minimal clearance between the disc and the sprocket.

So, I think it would be difficult to find a caliper that would fit.

We considered offsetting the sprocket even further and making the face of the adaptor thinner to see if we could get a disc to fit. However, I wanted strength and correct chain alignment. So, this is the direction we went.

Matt

 

[spinningmagnets]

Per post at the top; John Rob Holmes is making 4-hole 110-BCD adapter, a 52T chainring is available for $40
http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=50#p539499

Chainring list (just one of several) high tooth-counts and custom chainrings can often be found on recumbent sites.
http://www.hostelshoppe.com/cgi-bin/search.pl?category=605000
Chainring BCD guide
http://www.hostelshoppe.com/tech_bolt_circle_diameter.php
16 pages of 130mm chainrings
http://www.bikeman.com/130mm_5-Bolt_Chainrings.html

38T-60T Vuelta ($20-$36)
38T-53T FSA ($25-$50)
60T/65T Schlumpf ($95/$125)
62T Rans ($52)
73T Greenspeed ($190)

 

[boostjuice]

http://www.cycleunderground.com.au/chainringdesigns.htm
This Australian business makes custom chainrings for very reasonable prices. Although it says 56T is the maximum tooth count on the website, they do larger tooth-counts upon request all the way up to the ridiculous 100T+. All with the option of different BCD's, chain widths, plate thicknesses, designs and finish (anodized/polished). i got a 59T chainring from them and the quality is top notch and rare sizes priced better than any specialty recumbent website.

Also interesting for those who dont need large reductions at the rear hub http://www.cycleunderground.com.au/productcomingsoon.htm

 

[spinningmagnets]

Matt, I have linked to this thread in the "non-hub resources" stickie. If you want me to add, change, or delete it, you need only to contact me.

JohnRobHolmes, Do you have a link to your disc-brake 110-BCD adapter?

 

[johnrobholmes]

I don't have a link yet. That reminds me I need to call the shop that has the work

JRH

 

[dozentrio]

This is great, but I want it to freewheel too! So far a simple solution to this has eluded me.

 

[recumpence]

The freewheel goes on the output shaft from the drive unit.

Matt

 

[dozentrio]

.

 

[deecanio]

very very nice Matt.
I'm hoping if the dual freewheel drive takes off sucessfully you can do us some eno/extron adapters in the same vain???
oh man, so much good kit coming from you these days, really looking forward to the motor too

D

 

[illchilla09]

Hi,I would be interested in purchasing one of these adapters.How could I get one?Is there a website I could order it from?Thanks

 

[TopCat]

Hi,I would be interested in purchasing one of these adapters.How could I get one?Is there a website I could order it from?Thanks

Send Recumbence/Matt A PM and he'll sort one out for your.

Regards
Tom