GnG mid-drive kit

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
Morning all,

While waiting for my GnG 250w (new version) crank-drive kit to arrive, I've been pondering;

How does the supplied crank+chainring fix with the existing 3-ring chainset on the bike?

There doesn't seem to be much of this kind of info on the website, but Jon is very good at keeping one informed as to shipping, customs declarations etc. I've got loads of .jpgs of the kit, box & paperwork.

I ordered a crank remover & a BB spline socket from Chain Reaction & they were here next day: Excellent service - just hope they are not made of cheese, but they certainly feel decent.

It's a shame the new speedict is delayed, but better they get the firm/software right first-off: Vapourware is always a pain in the jacksie. Danny @ speedict seems to have gone a bit quiet, both on E/S & email.

Was it just me or did others have any problem with E/S earlier this week?
 

morphix

Esteemed Pedelecer
Oct 24, 2010
2,163
119
Worcestershire
www.cyclecharge.org.uk
Morning all,

It's a shame the new speedict is delayed, but better they get the firm/software right first-off: Vapourware is always a pain in the jacksie. Danny @ speedict seems to have gone a bit quiet, both on E/S & email.

Was it just me or did others have any problem with E/S earlier this week?
Yeah tis a shame, I'm hoping mine will arrive in time for my freewheel delivery or after Catsnapper is done with building my wheel so I can get a few rides in before the weather turns proper winter.

I agree though, better they get it right first time and have it take longer, than rush orders with shoddy firmware. I'd sooner wait. I don't follow ES much so appreciate the updates :)

You know, I actually contacted Speedict to enquire about selling it here in the UK as a distributor as I'm so impressed with it. But they just ignored my enquiries and I get the impression they want to keep everything in China and not work with distributors. Pity.
 
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vhfman

Pedelecer
Oct 5, 2008
144
0
Jackhandy, ES site was down for 10 hrs yesterday due to some memory issues on their server I believe, seems to be working fine again today.

As regards your GNG mid drive when you say 250W new version I presume you mean this one
24V 250W middrive

If it’s the same arrangement as the 450W mid drive, you will be replacing the BB and your 3 chainring set, with the GNG BB and crank set which has 2 chainrings. The outer 44T ring which is driven by the chain around the motor sprocket and tensioner. The inner one is 38T which drives a chain to your rear sprockets/derailleur.
Have you got a Chain Breaker Splitter; and you may need a 2 Peg Bottom Bracket Spanner like this, 2 Peg Bottom Bracket Spanner | eBay to tighten the GNG BB lock ring.


I’ve been using the 450W Brushless version for 2 months with a 36v controller. Hill climbing with the mid drive is great most essential in my location on the edge of the Peak District. I have an 800 Ft climb in the first mile up to the shops, with some steep bits, over 15% slopes.

Also waiting for the new Speedict . Seems like the China postal/customs service is slow at the moment. I have been waiting for a controller; it has been delayed at the SHANGHAI Delivery Agent for nearly 2 weeks. It was much better when I ordered my GNG about 2 months ago, it arrived in 3 days, and Jon was great with email top service.

I am interested in the new GNG2 drive looks like it might be good on my folding bike; yet another project! Will see how others get on with it first now that winter is approaching.
36V350W/48V400W geared mid drive brushless kit

Chris
 

rpurchon

Pedelecer
Sep 22, 2012
55
0
i have just orderd a 450w from a uk ebay seller [mateen233] does other e bike stuff.
i will be using 12s lipos 5ah or 10ah.what sort of range will i get with 5000mah.hilly but nothing as bad as you.
have you had any problems with the belt drive..
richard
 
D

Deleted member 4366

Guest
There's a new 400w brushless kit from GNG that's very tidy. Have a look on their website.
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
Hi Chris
Yes that's the one but I've ordered the 36v one.
The faqs say it works with 24 gear bikes &that you can change gear so I'm hoping it accomodates 3 front chainrings.
My saracen is gonna be disappointed if it doesn't, because I want it for some (up to 28% ) forest tracks & lanes I can't manage on the hub drive bike.
I am hoping to get away with using a spare angle grinder spanner with 2 pins to tighten the bb (with a bit of mod).

I live in a hilly area too - we are at 700ft. And some of my favourite rides hit sea-level so there's always a climb to get home; but I'm hoping 250w will do the job.

And for those who reckon theres no 28% hills in cornwall.... See following pics.
 
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vhfman

Pedelecer
Oct 5, 2008
144
0
Ok Richard you’re getting the 450W GNG drive on UK ebay.

I only use a 7Ah 12s A123 battery, and with all the hills and my reduced voltage system and controller, I average 24Wh/mile which is not very efficient; so approximately 11miles range. If you have less hilly terrain and you put more pedalling effort in, you may be get 12-15miles with 5Ah.

I am a rather weak and heavy rider, so it’s always difficult to assess what others might achieve. I am also using the Nuvinci N360 hub so not sure how much I am loosing through that, compared with a derailleur geared system.

The belt is holding up well so far; but long term it could be a problem if indications on the Endless Sphere forum are to be followed. I do try to pedal first to get some momentum before applying power, and I feed in the power rather gently, i.e. not doing wheelies.

The belt is rapped round the motor’s small drive pulley and tensioned with a rather crude bearing arrangement which I may have a look at modifying when the belt does go.
I also found that the supplied spring on the chain tensioner drive side was much too strong.

I’m using a thumb throttle as I feel I have more control with that compared to the full grip twist. But that’s a personal impression and the twist grip may be fine for others.

I wonder what bike you’re converting.

Anyhow best of luck with your build.

Chris
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
rps20121124_hustyn mill hill.jpg

Doesn't look too bad does it?

This is where the last one was taken from
rps20121124_28%.jpg
And is just about where my legs, and the hub motored bike, gave out :p
 

vhfman

Pedelecer
Oct 5, 2008
144
0
I fear jackhandy that you will not be able to get 3 chainrings on the BB, but I may be wrong.
Even with 8 gears you should have a fair amont of power from the set up for hill climbing. With my set up there is plenty of torque for low speed climbing on muddy tracks. I hope the brushed motor and gear box isn't going to be too noisy though.

Good luck with your build when stuff arrives from China.

Chris
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
I hope the brushed motor and gear box isn't going to be too noisy though.

Good luck with your build when stuff arrives from China.

Chris[/QUOTE]

It'll give the twitchers summat to moan about if it is :)

Hmmm - get up the steep tracks, or pedal like stink the rest of the time....

Ho hum....
 

vhfman

Pedelecer
Oct 5, 2008
144
0
Impressive hills and nice country tracks there. I've just been looking at the area around Hustyn and Bishop's Wood on Google Earth. As you say some times the slope of the hill is difficult to show in 2D, but the 28% road sign is a good indication.
I take video of my trips out in the hills and the shots never look as impressive on screen as they are in real life on the ground.

Chris
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
Yuss - it's a lovely area: I often join the camel trail at Nanstallon then head for either Padstow or Blisland for a pint, back to Grogley Halt then home through Ruthern Bridge, Tremore Bridge & home to Roche: Takes me past Bishops & Hustyn woods.

I've been videoing my rides & will get round to putting some routes on Cycle Routes over the winter (Next best thing to riding).
 

alfie

Pedelecer
Jul 20, 2011
43
0
The kit that is being fitted in the video is not the same as the picture of the new 250w kit! The new kit seems to be the old 250w kit with the housing extended so that it slots around both sides of the BB. It also has a sealed cartridge BB replacement instead of the spindle of the old kit. Both worthwhile improvements I think. Otherwise same as old kit?

The problem with this kit is that it only has a 38t crankset and this can't be replaced because of the positioning of the drive gear. This seems to limit the set of good match donor bikes. Like donor bikes with nexus or alfine hubs that seem to often come with 38t cranksets. The guy on the GNG forum who fitted the old version of the kit also needed spacers to align the bracket horizontally.
 
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jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
You're quite right - those changes do look worth having - that's why I'm paying the extra :p

I'm hoping the new crankset takes alternative chainrings: The pictures are none too clear, but it appears to just come with the outer motor drive ring, leaving the user to add a front set.

Should find out in a few days.
 

rpurchon

Pedelecer
Sep 22, 2012
55
0
hoping to get 10 miles from 5000mah.i pedal all the time.going on a old raleigh hybrid to start with.use it on the the road canal towpath.ive got a spare ecrazyman 6 fet controler so will try with that at 15 amps .i will try it with a shorter belt without tensioner.if its to my liking probably get a mountain bike and up the battery capacity.
thanks richard
 

alfie

Pedelecer
Jul 20, 2011
43
0
If its like the old kit the crankset has to be replaced with the kit set because it has a freewheel. It is only a single ring that is pulled via the direct drive motor cog. It means your limited to 38t because otherwise it collides with direct drive cog.
 

Old_Dave

Esteemed Pedelecer
Sep 15, 2012
1,211
2
Dumfries & Galloway
otherwise it collides with direct drive cog.
Yep, spent ages trying to figure a way around that one, but the man from delmonte said no.. unless the mounting plate was redesigned

38t chainwheel must of been thought to be a good idea, but by whom and for what possible reason kinda eludes me... maybe they forgot to take into account that the motor assists the freewheel speed :p

My fix was to not bother peddling and enjoy the ride
 

alfie

Pedelecer
Jul 20, 2011
43
0
My fix was to not bother peddling and enjoy the ride
:)

I brought the kit two weeks ago and have finally ordered a bike for it.

Because of the 38t restriction I looked at Nexus and alfine powered bikes and this was the final list of candidates for a doner bike.

Fuji Comp 7 Light - Mens | Buy Online | ChainReactionCycles.com

Ventura Future Commuter Hybrid Bike 2011 | JE James Cycles

Halcyon Aquilla Low Step Through Unisex Bike ONLY £300.00 [ 10HALCAQUIL ] - Discount Cycles Direct - Top Quality Brands at Discounted Prices

Saracen, Urban Clever Mike 2011 Hybrid Bike from only £499.99. Free UK Delivery | Wheelies

Bikes 2U Direct -- Leisure bikes : Traditional -- Ridgeback Avenida 8D green ladies

The Saracen was too small
The Ridgeback and Halcyon would avoid the problem of castration by a to high crossbar or by the wife for buying another bike but also leave my street cred in negative equity.

Leaving the Ventura or Fuji.

It looked like the Fuji was the only choice because of the eccentric BB on the Ventura and then I had the idea that I could orientate the BB forward so that the kit had more room for the brackets to fit. Simply attach a chain tensioner on the right rear dropout. So the problem might actually be an advantage.

Three speed is more than enough for my commute so I pulled the trigger on the Ventura today. It being the cheapest also had something to do with it.:D

Possible problems: the kit wont fit the rear stay, The bike will be too tall and castrate me, the rear dropout hasn't got a derailleur port so difficult to fit tensioner ...:eek:
 

Old_Dave

Esteemed Pedelecer
Sep 15, 2012
1,211
2
Dumfries & Galloway
Possible solutions...

Remove the existing stay and get one that fits to the rear triangle (like wot I had to do, lol)

The rear wheel possibly has front/back movement to adjust the chain, so if you get your chain length just right, then a separate tensioner won't be needed


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Old_Dave

Esteemed Pedelecer
Sep 15, 2012
1,211
2
Dumfries & Galloway
Opposite sorry, I was referring to the stand.. Not the stay


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