Patterson 2 speed

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waynebergman
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Patterson 2 speed

Post by waynebergman » Dec 24, 2017 6:51 pm

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I am not so familiar with these Patterson Crank sets but they sound interesting. With my Bafang HD 1000 it would be nice to be able to catch up to the motor with pedal input for road rides and having a little taller gearing would be nice. I am running a Sturmey 3 speed on the rear so there is not a lot of range with these 3 gears. Gives me a great chain line and fairly trouble free, but it would be nice to have a little taller gearing from time to time and also keep my nice chain line.

Does anyone know if something like Patterson two speed crank could be installed on a Bafang HD 1000 drive BB spindle? Not that I need the 6 speeds this would give me driving the Sturmey, two would be plenty - but I want a bigger spread from low to high and this unit sounds like it would do the trick if I could somehow mount it on the drive unit.

Thanks .......wayne

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Re: Patterson 2 speed

Post by Chalo » Dec 24, 2017 7:16 pm

The Patterson crank is a unit that installs in the frame basically the same way as the BBSHD does. You can use one or the other.

Patterson/Schlumpf/Hammerschmidt cranks would make sense when used with geared hub motors, to give two very different gear ranges for operating with and without electric assist.
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Re: Patterson 2 speed

Post by fechter » Dec 24, 2017 10:11 pm

I've often wanted a higher gearing with the pedals on my BBSHD but need to keep it in low gear to avoid overheating on steep climbs.
Unfortunately the Patterson unit can't be easily adapted to work with a BBSxx drive. This would be something Bafang would need to do from the start.

I could envision something like the guts of a Rohloff built into a mid drive unit so you can just run a single rear sprocket. For ebikes you don't need so many speeds.
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Re: Patterson 2 speed

Post by amberwolf » Dec 25, 2017 1:23 am

If you have the space for it, you can do what I did with SB Cruiser, and stick an IGH between the cranks and the wheel. Not all bikes could do it, but some could. Would require making mounting plates to simulate dropouts to hold the IGH, and might require redirecting teh chainline around the stays differently tahn it is now.

If everything is already a fixed chainline on an IGH in the wheel then it would be easier than when the chainline has to move around & shrink/grow.

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Re: Patterson 2 speed

Post by waynebergman » Dec 25, 2017 11:36 am

Hey thanks guys. Now I know. I guess at this time the only real solution is the super expensive rohloff hub but I just can not justify spending that kind of money. Also with my electric running around 1500 watts I certainly don't need 14 speeds, I only really need two or three at most bust just a larger ratio between first and third gear.Too bad there isn't an affordable IGH with some decent range between the 3 gears. One option also would be to pull the 30 tooth mini on the front and go with the original Luna Eclipse ring and swap out to longer chain for road rides but I am too lazy to do this as I go back and forth between road and trail rides from time to time. Still happy with the bike as is now just not perfect. I will keep my eyes on new offerings for IGH maybe someone will come up with a product that has some better gearing range.

On a different topic one more product that would be cool but no one is making as yet is a suspension seat post that is also a dropper post. As my bike is a hard tail the suspension post is nice but for the trails I like the dropper post. No one makes a combination unit that I can find. I guess most of the hardtail riders out there are happy enough with one or the other so there is not enough of a market out there for developing a combination post like I would like.

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Re: Patterson 2 speed

Post by AWD » Dec 26, 2017 9:10 am

I have been using Schlumpf's for years. I have them on my e road bikes that have front hub motors because they give me the range of gearing I want to keep my cadence and the motor input coordinated.
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It is too bad that there isn't a mid drive with this feature but it would have to be pretty complex. My suggestion would be to either go with an 8/11 spd Alfine, which would net you a bit higher gear or sacrifice perfect chain line while in road mode by using a derailleur/freewheel/cassette with as few of cogs as you need. I am looking at resetting my rear triangle on my recent mid drive build in the interest of better chain line, we'll see how that goes. For sure it is nice to have the range of gearing that you need on board though, especially if you like to pedal along.

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Re: Patterson 2 speed

Post by waynebergman » Dec 26, 2017 10:53 am

Thanks AWD, even though the ratios are better on the two hubs you are suggesting I have read that they are not as strong as the 3 speeds. I have already had the planet gears fail on my three speed so not wanting to take a chance on anything that is supposed to be weaker than what I already have got. Also I have 170mm rear dropout spacing, fat bike.

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Re: Patterson 2 speed

Post by LewTwo » Dec 26, 2017 6:26 pm

Stupid question: Is it possible (practical) to put a second chain ring on the bafang mid drive?
One might not require a derailleur but rather do a manual chain change for the appropriate range for a given ride.
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Re: Patterson 2 speed

Post by maydaverave » Dec 26, 2017 8:14 pm

I put one on a bike, the soft aluminum crank bolt quickly stripped, they dont sell replacements, and its a non typical size and threading. i Took what was left of the bolt to a bolt and fastener shop and they had never seen that particular thread pattern. So long story short i got about 20 miles out of it.
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Re: Patterson 2 speed

Post by Chalo » Dec 27, 2017 5:43 am

maydaverave wrote:
Dec 26, 2017 8:14 pm
I put one on a bike, the soft aluminum crank bolt quickly stripped, they dont sell replacements, and its a non typical size and threading. i Took what was left of the bolt to a bolt and fastener shop and they had never seen that particular thread pattern. So long story short i got about 20 miles out of it.
A competent local bike shop can get you replacement parts for an item that's currently in production. As an individual user, you may or may not be able to get it yourself. I'll bet FSA would at least give you a part number of you emailed them.

To be honest, in FSA's assembly instructions, the bolt looks a whole lot like this one, and has the same torque specification: https://shop.fullspeedahead.com/en/ml25 ... crank-bolt

0.7 to 1.5 Nm is not very much torque, so use a torque wrench or be extra careful.

Even industry-wide common fastener threading within the bicycle industry isn't always available in industrial fasteners.
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Re: Patterson 2 speed

Post by maydaverave » Dec 28, 2017 4:46 pm

Chalo wrote:
Dec 27, 2017 5:43 am
maydaverave wrote:
Dec 26, 2017 8:14 pm
I put one on a bike, the soft aluminum crank bolt quickly stripped, they dont sell replacements, and its a non typical size and threading. i Took what was left of the bolt to a bolt and fastener shop and they had never seen that particular thread pattern. So long story short i got about 20 miles out of it.
A competent local bike shop can get you replacement parts for an item that's currently in production. As an individual user, you may or may not be able to get it yourself. I'll bet FSA would at least give you a part number of you emailed them.

To be honest, in FSA's assembly instructions, the bolt looks a whole lot like this one, and has the same torque specification: https://shop.fullspeedahead.com/en/ml25 ... crank-bolt

0.7 to 1.5 Nm is not very much torque, so use a torque wrench or be extra careful.

Even industry-wide common fastener threading within the bicycle industry isn't always available in industrial fasteners.
Thanks looks the same. I was hoping to replace with a steel bolt as the aluminum bolt couldn't handle my mighty girth.
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Re: Patterson 2 speed

Post by Chalo » Dec 28, 2017 10:12 pm

The spline on the spindle is supposed to deal with your girth and everybody else's. The bolt just keeps the thing from crawling away. That's why it has a very low torque rating.
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