2005 Kona Stinky GNG 1.0 build (mid-drive Stink-E) ABANDONED

[skyungjae]

cool bike, better get some coroplast ("used" political signs ), taped around those batteries. denting can wreck them and you will dent them if they are loose like that. coroplast notched and folded around with a bunch of duck tape works for me. also works with a few extra layers as a battery box on the bike as well

That's a good idea. Right now I just wrap them up, not too snug, with wide Velcro luggage straps with a plastic buckle on one end. I should probably put a layer of that coroplast in between.

 

[skyungjae]

Interesting - did not know they carried those packs - wonder how they compare to the Ping type 48v LIFEPO4 packs from china? The C rate is certainly impressive compared to the minimal C rate of the Ping packs - do they charge past the rated voltage when hot off the charger? Are you using the CA in place of a BMS? I will likely pick up two 6S 5000mh packs as a second battery but this is an interesting option as well

Sorry about the late response. I didn't see this question earlier, but hot off the charger it'll read out 49.8v on the multimeter after I series them up. That's only when I balance charge at 5A. The times I've checked charging at 10A balancing or not, it read 49.5v exactly.

 

[skyungjae]

My freewheel just came in today. I hope everything lines up right. There may be some clearance issues with the adapter and new freewheel. The Chain line from motor to large crank chainring may change as well. Unfortunately, since the last part to make this all work showed up today, things will have to wait until Sunday (Working from tomorrow until Saturday).

Here are some pictures of the jackshaft adapter and the ACS Crossfire 13T Freewheel:

I would have liked instead of having a groove machined in for that retaining ring that there was just a lock ring and a spanner wrench.

 

[dezellis]

Subscribing to topic to check on the progress.
I have a new kit and can visualise future belt drive problems.
Regards
Dez Ellis

 

[skyungjae]

Due to a family emergency I've taken some time off work. Took keep my mind of things, I decided to get started on things late at night. The upgrades I've made worked great until the retaining ring on the jackshaft freewheel adapter started peeling off.

I trimmed off the excess with a pair of dykes, and the rest of the ring is most likely wedged properly stopping the freewheel from twisting off. However, the chain line did change as a result, and I'm not a fan of losing half of the freewheel retaining ring.

Here are some more pictures:

That's the BikeMotive with the ACS CrossFire 13T freewheel. (Keep in mind, if you're going to go with a 13T, you'll probably have to use a half link as I did.)

Adapter mounted and spacing before the retaining ring started to peel. I bought some spare bushing spacers to adjust the chain line if need be, but I found it lining up the best with it as far on as possible bringing the chain closer to the bike.

Here's the sickbikeparts.com 48T chainring mounted to my 34T Blackspire chain ring(Thought it was a a 32T before cleaning it off) and sickbikeparts.com standard freewheel. It spins true in the forward direction and under motor and pedal power!

I had to get a new chain, due to the increased length and a half link (not a fan of this) to get it to work.

Pictures after human power test riding.

This is pretty much complete minus the issue with the retaining ring. I plan to keep the belt drive and replace the belts, with better quality ones, when needed. My new gearing is really made for climbing and not speed. It also helps that I usually don't bring the wattage and motor speed up all that high.

 

[skyungjae]

I decided to test the jackshaft freewheel adapter to see if the remaining pieces of the retaining ring would hold. After hitting my 44v LVC, it's managing to hold under full throttle in any gear as well as abrupt throttling. Here are the post pictures:

That's the part of the retaining ring that was coming off in the first picture of my previous post.

The remaining part of the retaining ring doing its job.

The chain line is now the same as the GNG 12T jackshaft freewheel.

Additional notes: I did not need to use the 104mm 4 bolt spider arm to mount my Blackspire Chainring to the sickbikeparts 48T large chainring. Though it doesn't show it on the website, the 48T chainring had the 4 holes with the proper 104mm spacing.

Additional additional notes: Get the Gen 2 kit and not worry about a belt, jackshaft, jackshaft freewheel. :wink:

 

[speedmd]

Looks good. Local bike shop will have a lock ring for the threaded adapter most likely and I would lock it against the freewheel and loctite the two to the adapter. Use the strong stuff good for gluing bearings to shafts. Will easily come apart with some added heat when it is worn out.

 

[christerljung]

Great pictures, and detailed mod instructions. Thanks!
I just ordered the freewheel adapter since my own GNG-freewheel fell apart.
Why did you change the crank?
btw, the gen 2 GNG has a lower power output and smaller motor.

 

[flyinmonkie]

You can use a bottom bracket lock ring from an old 3 piece bottom bracket to lock the freewheel on the adapter. They are the same thread as a standard freewheel. Make sure you use one with the same thread though, left or right hand.

For the crank, can you put a new freeewheel in the GNG mount so you don't loose the support bearing? That will help the freewheel in the crank last longer. Or is it the mount that is not true?

Clay

 

[full-throttle]

You can use a bottom bracket lock ring from an old 3 piece bottom bracket to lock the freewheel on the adapter. They are the same thread as a standard freewheel.

The 13t freewheel uses a smaller 30mm dia thread.

 

[skyungjae]

You can use a bottom bracket lock ring from an old 3 piece bottom bracket to lock the freewheel on the adapter. They are the same thread as a standard freewheel. Make sure you use one with the same thread though, left or right hand.

For the crank, can you put a new freeewheel in the GNG mount so you don't loose the support bearing? That will help the freewheel in the crank last longer. Or is it the mount that is not true?

Clay

The GNG crank arms are weak from the get go hence the stripped threads. The GNG chainrings and support bearing are proprietary and didn't spin true when pedaling (it would spin true under motor power) regardless of what 16T freewheel I was using. My new set up will allow me to upgrade to an ISIS BB later if need be and use whatever chainring I want.

I really don't want to spend anymore money on this kit. Hahaha

 

[skyungjae]

Great pictures, and detailed mod instructions. Thanks!
I just ordered the freewheel adapter since my own GNG-freewheel fell apart.
Why did you change the crank?
btw, the gen 2 GNG has a lower power output and smaller motor.

The crank arm that came with the kit stripped itself when I started pedaling with human power on the smallest rear cog, so I ordered some beefier once that sat about 7-8mm further out. Though I have a replacement GNG crank arm, the ones from BikeMotive (same specs as sickbikeparts.com) are simply much beefier and has more threads for the freewheel.

Right now I'm limited my output with the CA to 20A, so even at full throttle I'm shy of 1000w. 400w at 20a would probably be similar. I know the output and motor is smaller, but it's got to be more efficient getting rid of the belt and cross over jackshaft.

This came with my jackshaft freewheel adapter. Don't forget to pick up a half link if you go with a 13T freewheel.

 

[flyinmonkie]

fullthrottle... I missed the 13t bit of the freewheel. Yup, smaller diameter, but could work if you went up to an 14t.

skyungjae... I was meaning just the bit the freewheel mounts in and holds the support bearing. Use a different set of cranks and chain rings. Bit if than part didn't run true, there there is no point. I hope you have it sorted now. The freewheel crank has been the week part of all of the mid drive kits. We need to find parts that create a quality setup or hope a company comes up with a quality one soon. Keep an eye on fullthrottle's isis setup. Where are the pics by the way FT.

Clay

 

[skyungjae]

fullthrottle... I missed the 13t bit of the freewheel. Yup, smaller diameter, but could work if you went up to an 14t.

skyungjae... I was meaning just the bit the freewheel mounts in and holds the support bearing. Use a different set of cranks and chain rings. Bit if than part didn't run true, there there is no point. I hope you have it sorted now. The freewheel crank has been the week part of all of the mid drive kits. We need to find parts that create a quality setup or hope a company comes up with a quality one soon. Keep an eye on fullthrottle's isis setup. Where are the pics by the way FT.

Clay

What I noticed was the proprietary GNG chain ring (with the adapter and support bearings) did not rotate true while pedaling with any freewheel (only used two types, ACS and GNG) and with either crank (GNG and BikeMotive). The more I used the bike, the more off true it would become (probably due to the loose bearings in the ACS freewheel). Last I rode it, the chain on the smaller chain ring was getting dangerously close to the hex motor to mount bolt only when pedaling. The GNG Chain ring set up did rotate true when it was under motor power.

Though the sickbikeparts.com set up I have now doesn't have that support bearing. I was able to mount the chain rings closer together, and they both spin true pedaling and under motor power. The overall set up seems much more torquey and smooth. What's interesting is when I pedal backwards the chain rings will still oscillate. That's not a problem because the chain rings aren't rotating nor are the chains moving. As soon as I start pedaling or applying throttle, it spins true.

With a new, better quality freewheel, I'm sure the proprietary GNG chain ring and crank set up is fine for long term use. You're just stuck with that 38T and 44T chain ring pair. That's not necessarily a bad thing, but for those using heavy bikes like mine run the risk of stripping the crank threads and simply having a poor pedaling gear ratio.

In the future, I may pick up a Gen 2 motor and controller to use with my extra GNG parts on a much lighter bike.

 

[full-throttle]

Though I have a replacement GNG crank arm, the ones from BikeMotive (same specs as sickbikeparts.com) are simply much beefier and has more threads for the freewheel.

GNG keep changing the specs unfortunately. The crankarms that I've with my kit got are similar (if not the same) as the ones from sickbikes.com and the TryAll I've got recently.

BTW I've started a thread on bottom brackets /viewtopic.php?=47618

 

[skyungjae]

Back to the 12T jackshaft freewheel. After some riding today, it looks like more of the retaining ring is peeling. I've contacted BikeMotive about it day of, but they haven't responded yet.

 

[skyungjae]

Today's ride:
http://www.gmap-pedometer.com/?r=5817135

Route

Elevation change

I was able to keep a good speed on the flats and steady inclines about (10-15mph) while pedaling. On the steeper uphills, I would drop it into a lower gear and go up the hills between 3-10mph depending on how steep it was. The trail terrain has a lot of erosion from the recent rain, so I had to slow down and choose my lines carefully. On the final incline from mile 7, I used a lot more throttle keeping it closer to 15mph. I started hitting my LVC on the last downhill toward my townhouse complex.

I must say... I'm pretty darned happy with my set up.

 

[skyungjae]

Well, that jackshaft freewheel adapter seems be very stubborn. I'm trying to take off the ACS Crossfire using the proper tools, but it just seems fused on. Regardless of using a vice and a bolt/nut & washers to hold the tools on, it's impossible to get the required torque to keep the Park Tool SPA-2 on the freewheel adapter. It's popped out a couple of times starting to create a ramp on the two holes on the adapter. My big bertha flat tip screw driver fits well in the key indent, but I can't secure the handle or get enough torque twisting that or twisting it in conjunction with the SPA-2. I'm going to try an impact gun as a last resort. Also, BikeMotive has not gotten back to me regarding replacing the retaining ring. I may have just wasted about $70 trying to find a jackshaft freewheel replacement solution.

This adapter is probably still good for those looking to replace their 12T jackshaft freewheel. Just gotta do something about that retaining ring. Maybe get it more snug before applying motor power or getting some sort of snap ring or a M30 jam nut to work in conjunction with it.

Update:

IMPACT GUN!!!

 

[skyungjae]

Tonight's ride:

I decided to do the west of Harbor Blvd. "Fullerton Loop" just for the hell of it tonight. I was able to complete it in 1:03:53 (1 hour, 3 minutes, 53 seconds). Having only done 5A charges, I thought I'd charge and balance the pack at 2A. It took 2 hours from were the pack was already at (last I used it was just in the neighborhood). Anyhow, the pack performed extremely well. I used it mostly on the uphills and flats to keep my speed up while pedaling. I started with 49.5v. It's been about an hour since I unplugged it from the CA, but now it's reading 48.3v (probably because it's warmer inside). I do recall it being 47.Xv unplugging it pulling up to the garage, but I as impressed on how well the batteries held up.

I could have done it faster had my chain not fallen off twice on the really bumpy downhills. Also, on the last downhill, my left crank came loose and started wobbling. I had to use mostly motor power on the final incline and the way into my neighborhood.

I was getting disappointed in my battery pack, but I think the HVC of my charger hits when the any of the 5 batteries reaches capacity leaving the rest not fully charged. Charging at 5A in under an hour probably wasn't helping. I'll make it a habit to balance all the batteries at least once a week at 2A.

As for my jackshaft adapter, I think I've found a suitable replacement for the retaining ring:
http://www.fastenal.com/web/products/detail.ex?sku=1135326

The groove is 1.5mm thick, so this should fit nicely. I'll stop by a local distributor on Tuesday.

 

[skyungjae]

Now here's my dilemma: This set up is more than likely going to fail

Yep. Your next problem will be the bottom bracket spindle bending. I've ordered Truvativ Hammersmidt BB and will get ISIS crank arms. Already got WI FW. Will let you know if it works.

Nice build BTW

Well, looks like you were right. This morning, my rear tire was flat. I did hit a hard dip that dislodged my chain on one of the downhills last night. This must have been what warped my BB spindle. I noticed today after test riding the bike with the Fastenal 30mm snap ring (which works fantastic). It did make my heart sink to find out something else had gone terribly wrong. I do have a spare GNG BB, but I know it's only going to bend in the same way.

Anyhow, here are some pictures of the Fastenal 30mm snap ring:

It came out to $2.07 at the local Fastenal distributor for 3 snap rings.

 

[skyungjae]

Yesterday I decided to do a test run on the North West part of Fullerton Loop (where all the fun hills and jumps are ). It started raining on me about a 1/4 way in, but I was able to get through it before it got muddy.

The 30mm snap ring is holding great on the jackshaft freewheel adapter, and the ACS Crossfire 13T is super smooth. I guess the one downside is that the racheting clicks are spaced closer together. It's not louder, but the clicks/ticking sound from the 13T freewheel is more rapid if you get the idea.

Since the left side of my bottom bracket spindle was bent, it would cause the crank bolt to loosen and the crank arm would wobble loose (I could remove the crank by hand without using a crank puller). I decided to put some red/permanent thread locker on it on Monday, and it held up well jumping off railroad ties and small jumps on the trail. I pedal a lot, but I can live with this at the moment. Switching back and forth on my new Giant Roam (Picked up on Monday), I can tell that the left crank on the Stink-E is a bit off, but only very slightly.

I feel that I have a couple of options regarding dealing with the bent bottom bracket spindle:

1. Wait for an ISIS solution for ISIS crank arms. That means more money spent on crank arms and a new bottom bracket.
2. Get rid of the crank freewheel and run "pedal assist" style (no coasting) with the ISIS BB and Cranks I pulled off the bike. Not too bad of an option since I'm always pedaling when engaging the throttle.
3. Swap in my spare GNG BB. Problem with that is it'll more than likely bend in the same fashion after a few trail rides.

Another issue that I'm running into is my chain falling off going down flights of stairs, rough terrain, and/or hitting hard dips/bumps. Having a DH bike with a lot of rear suspension travel, it was almost a necessity to have my Blackspire chain tensioner and idler. My chain would still fall off from time to time, but not EVERY ride (more than once on longer rides). Due to the way the GNG is mounted, I had to do away with the tensioner and idler. I was thinking about making my own PVC chain guide, but decided to pick up one of these instead (looks way cooler than anything I'd be able to rig :lol: ).

Hopefully this will remedy the chain from jumping off.

As for a potential crank solution, I may go with #2 and do away with the crank arm freewheel... not to mention, I can use my Blackspire chain tensioner and idler again.

I'll keep y'all updated.

 

[flyinmonkie]

Be real careful if you decide to go without the freewheel crank Getting a pedal slammed into a shin or calf under motor power would be nasty. It would be easy to do by mistake even if you just bumped the throttle a little on accident.

Clay

 

[skyungjae]

Be real careful if you decide to go without the freewheel crank Getting a pedal slammed into a shin or calf under motor power would be nasty. It would be easy to do by mistake even if you just bumped the throttle a little on accident.

Clay

Thanks for your concern. I'm probably going to wait it out until someone finds a solution to the weak BB spindle. I'm certainly not the only one who's bent theirs, and I won't be the last. There are some things I want to try, but don't have the funds right now. Well, I got the funds, but my accountant wife was pretty pissed about all the bike related parts I've been purchasing in the past 2 months.

 

[rjoe]

bolo yeung!

 

[skyungjae]

bolo yeung!

"DAHHH!" Bolo - Enter the Dragon