E-S Stealth Electric Bike Owners

[Rix]

Kepler,

I just emailed Stealth this morning about the issue and they already got back to me. (Wow that was fast) The US rep Darrin said he needed to speak with an engineer at Stealth tonight local time and said whatever resolution they needed to come up with will be covered by warranty. I am really impressed with Stealth's customer service/feedback. So for now, I wont be doing in welding or reingineering myself in leau of warranty coverage.

Rix

[Hyena]

I've had regen issues too but then I'm using an aftermarket motor with more power so it's not something I can really call stealth out on. Though Kepler is running higher power too and has had no issues so who knows.

Don't go welding to the axle though, modding the torque arm is definately a safer bet. This sounds like more of a QC issue with the TA (bad machining / laser cutting ? for a less than tight fit) and it's good that stealth are sorting it. Though knowing crystalytes varying degrees of QC I wouldn't be surpised if it was the axle itself that wasn't properly machined. An ideal solution would be a clamping torque arm insert to replace your existing one. Basically a longer version of what's supplied but with an open slot and a pinch bolt on the end. You'd lose the tensioner adjustment but how necessary are they on an ebike anyway? I don't bother with them and tighten up my axle nuts first and then nip the tensioners up afterwards just so they're not rattling around

[cruzxia]

The pinch bolt is a good solution to clamp the axle using a thicker redesigned chain adjuster.
The problem is that as you clamp the axle the adjuster moves away from the swing arm, because you are making it narrower by clamping the axle. It would be better than the current setup, but not perfect, as the adjuster plate could rotate.

It would prevent the nut undoing, as if the axle rotates, the adjuster plate and nut would rotate with it.

I considered this idea, before designing my torque arm.

Cruzxia

[Rix]

Kepler, Hyena and Cruz,

Dont I feel stupid. I don't have a torque arm. I should have noticed this when I removed the rear wheel and installed the Tuffy Tire liner between the tube and tire. Unless the axel blocks are also considered the torque arms. Here is a close up pick of both sides of the hub axel and swingarm dropouts. It looks like Stealth eliminated the need for a torque arm by the way the cut the swingarm dropouts and axel adjuster blocks. The dropouts are cut so that the hub motor axel can only be installled by sliding into the dropouts sideways with flat ground portion of the axel facing up and down. Same with the axel blocks. I guess this design would eliminates the need for a torque arm. I don't know what the Stealth Engineers will do to fix this, but I can tell you what ever the process involves, it will have keep the hub motor axel from having any rotational play when installed in the dropouts on the swingarm. I loosend the axel nuts all the way and rotated the wheel forward and backward. There is just a tiny bit of play that I can feel. Apparently thats enough though. Its either coming from the axel blocks and swingarm dropouts, or tolerance of the axel itself in the swingarm dropouts and axel blocks. For the mean time, im going to do what Kepler suggested and try shimming the blocks with 4mm washer. No voided warranty concerns with this. Cruzxia, you having of the flange nuts and custom torque arms for sale? I found some M14 1.5 pitch grade 5 titanium flange nuts on the net for 23 bucks a piece. I would rather stick with steel though. I will let you guys know what stealth says.

Rix

[Kepler]

Its our general terminology that has confused you. We are considering the blocks used to adjust the wheel position and chain tension to be the bike's torque arms. So as with all Stealth bikes, you do have torque arms. Go with plan "A" for now and see if you can shim the "torque arms" with the washers. I think the introduction of regen has been the main cause so if they still come loose, definitely stop using the regen until the factory gets back to you. I will be interested to see what they come up with.

[Hyena]

Yep as Kelper said what were describing ARE torque arms, it's just hte shape of the frame holds them in place rather than needing to be bolted in like many others.

Cruzxia, I agree having a pinch type insert would deform slightly when tightened but it'd be minor. One solution would be for stealth to weld in the "torque arm" so the last rear inch of the bike became essentially a thick drop out. Then you could pinch bolt it tight and have no worries. It wouldn't be replacable like the current one but it wouldn't need to be as it'd be super strong and the axle would be going no where.
On mine where there has been a slight bit of play the axle has slightly deformed the TAs, chewing slightly threaded grooves into the edge of the 10mm flat (but as stated previously this is with higher power so not really stealths issue)

Also on an unrelated note, any stealth owners that have missed the not so subtle notice in my signature - there's a ebike group ride in Sydney this weekend. It's looking like we'll have 2 fighters there but I know there's more stealth owners in Sydney so it'd be great if more came along. Click on the link in my sig for details

[remf]

I'd like to be there but I'm not in Sydney at the moment. Not only that but my Fighter is in pieces waiting for new bits. Next best thing...some of your usual HD goodness.

[Hyena]

No worries, hopefully we can get some more ride happening down the track.
My fighter is in pieces too, gotta lace up a new rear wheel before Sunday!

[Rix]

Kepler, Hyena, and Cruzxia,

Found the solution!!! Last night I squeezed two 4mm flat washer between the axel block and the swingarm drop out lip and went for a 13 mile ride using the crap out of my Regen. It stayed tight. I contaced Darrin (US Rep) and suggested that the Stealth "parts guy" go through the axel block (Torque Arm) bins and mic the the thickness of them top to bottom. If he can find two that are slightly thicker (.020) or thicker difference, send them to me. Kepler, sorry about the terminology confusion, in the gasser world those are referefed to as "adjustable axel blocks" and I am using gasser terminology to describe Ebike stuff which I am like a whitebelt cooley compared to you guys who are like 5th degree blackbelts. But I am learning slowly. Anyway back to the torque arms, your suggestion with the 4mm washers proved to be the solution. Thank you. I will be riding Lake Tahoe tomorrow and will post some pics. You guys have a good weekend.

Rix

[Rix]

Kepler,

Went home at lunch and snapped some pics of the washer shim mod. Its ghetto, but its working so far.

Rix

[cruzxia]

Rix

Great that that is working. All you need to do now is put a spot of weld on the adjuster plate where you placed the washer, and then file it down to a perfect zero clearance fit.
As suggested, I would like to be able to offer the flange nuts and torque arm that I made, but they take to long to make by hand, If they were CNC machined, they would be low cost to produce. I did send photos to John, I think that I will mail him the 2 spare flange nuts to try.

Cruzxia

[Kepler]

Interesting. That's not what I was expecting. I was thinking the shim needed to go between the motor axle and torque arm, not the torque arm and the and the swing arm dropouts.

I would have thought by having the axle adjusting bolts tight, you couldn't have any movement there. When I tighten my motor up, I nip up the main motor bolts then adjust the chain tension and wheel alignment with axle adjusting bolts. I then tighten up the motor axle bolts nice tight and finish off with then tightening up the axle adjusting bolts nice and firmly. This way I am making sure the torque arm doesn't rock.

It may well be that the tolerances need to be looked at though.

I went and visited John at the factory yesterday and discussed this issue with him. He is looking at a few options at the moment to remedy the problem.

[Hyena]

Here's a few pics of my fighter which is nearing completion - until I change my mind and reconfigure it all over again

I've drilled the larger 40mm motor which while probably unnecessary will let me run even more power The windings were pristine after a few months of 7kw peaks but it'll run even cooler now, letting my ride harder for longer. I've fitted an internal 100 degree thermostat inline with the hall voltage line which will essentially kill power to the motor in the event it gets too hot. 100 degrees is pretty conservative too but I'd rather be on the safe side. With my health being the way it is I couldn't push the bike home with a melted winding or even pedal it very far unpowered - but I CAN sit on a log for 10 minutes until the thermostat resets and then ride home a bit easier

My lipo charging solution is nearly finished. Balancing and isolated cell charging will happen though the centronics plug in the original CA location. This allows charging of individual cells at 8 amps which makes very short work of balancing. I could charge the battery only this way but charging at 8 amps is for suckers I'll use it just for balancing occasionally, which will only take minutes with this set up. Main charging will be done with a home made 2400w super fast charger - the most powerful one I can run on a standard house mains AC outlet This will charge the 18S 18ah pack at 32 amps - just under 2C fror a 90% recharge in around 30 minutes. I've also replaced the standard key with a motorbike one which has a second click for accessories. First click turns on the bike, second click turns on the internal DC-DC converter which powers the lights (not yet fitted)

8 amp balance charging

fighter3-ES.jpg (155.31 KiB) Viewed 397 times

I've also removed the 3" halo knobby (and what a task that was!) and replaced it with a DMR motoRT which is more suited to the sort of riding I do. Not as slick as the crazy bob but still rolls fast on the road and hard trails. It's quite similar to the berm master actually.

(click for bigger pics)

[cruzxia]

Axle clamping
I would guess that by pushing the adjuster plate down with the shim, it is clamping the axle on the top with the adjuster plate, and the underside of the axle is pressing on the swing arm. So it is acting like an axle clamp.

Hyena, Great looking fighter you have there, I bet it flys at 7kw. I like your balance connector idea 1 plug is the way to go. That is a rapid charging plan you have. Is your charger adjustable (current wise), Charging a a lower rate when you are not in a rush, will prolong cell life.

[Kepler]

Here's a few pics of my fighter which is nearing completion - until I change my mind and reconfigure it all over again

Nice work Hyena.

I think this bike is arguably the number 1 hub powered ebike on the forum (in my opinion ). Although there are lots of great bikes here, I dont think any of them can match the combination of reliable hi power, reasonable weight and big battery capacity, all wrapped up in one of the best ebike frames around.

Great work and cudos for doing it your way

[Rix]

Hyena,

WOW!! Your fighter is Awsome! That thing looks wicked with the vented hub and the zock forks. 7KW with 18s. I am guessing between 90 and 100 amps. Got Torque?

Cruzxia,
I may end up tac welding the washer and form fitting. So far its working great. Did a 30 miler yesterday and no problems.

Kepler,
I appreciate you inquiring at the factory about the problem I was having. I have a temp fix with the washer but I think I know why my axel nuts keep coming loose. The post on one of my torque blocks was bent pretty good. I have straightend it a little but its still bent slightly. Anyway when I snug up the post face place against the end of the swingarm dropout after I tighten the axel nuts, the post plate isn't seating properly into the grove on the drop out. If you look at picture with the washer, you can see the plate isn't seated properly. Here is a pic of the post after I straightend it a little. I need to heat it with a torch to straighten the rest of the way. Still doen't seat evenlty but fits better than before.

Rix

Rix

[Kepler]

I think you could straighten that completely cold without a problem but if you have a torch, probably a better method. Will be interesting if once this is straight and is torqued up squarely on the back the dropout whether the problem continues to occur. With my discussions with John, he fully acknowledged the issue was there but was saying that he couldn't get it to occur at all with the factory testing.

Would be great if you could just fully straighten the adjustment stem and install using the method I described and see how it goes. Then if still moves, email John and get the OK off him to weld in the shim so as to protect your warranty.

[Hyena]

Hyena, Great looking fighter you have there, I bet it flys at 7kw. I like your balance connector idea 1 plug is the way to go. That is a rapid charging plan you have. Is your charger adjustable (current wise), Charging a a lower rate when you are not in a rush, will prolong cell life.

Yeah she goes OK Previously when out chasing dirt bikes and crawling over steep, rough terrain and thick mud (ie the worst thing you can do for any hub motor, let alone a higher speed wind) it got quite hot, not enough to burn my hand instantly but enough I couldn't keep it on the cover. After some hard riding yesterday it was barely warm so the air cooling has really helped. I don't really need any more top speed but I might up the voltage to 24S with a small external booster pack. I like round numbers and 10kw has a nice ring to it 6S 18ah will sit nicely in the low dip on the top of the frame and I can easily wire my charge port with a series link that can be removed to plugged in the extra booster voltage.
And yeah I have multiple chargers - the isolated balance charger (which could do the whole pack if I wanted) Also a 4 amp 18S bulk charger for slow, usually over night charging or when I'm not in a hurry. This charges to 75v (~4.16v/cell) and then if I'm going on a big ride like yesterday I'll balance charge it up to 4.19v. Incidently I used 16.5ah of the 18ah pack yesterday (doing 42km) and the cells were all well balanced at 3.5v at the end.
I also have a 20 amp 6S bulk charger (for parallel charging each sub pack @ 6.5a) and a 32 amp 6S bulk charger (for parallel charging each sub pack @ just over 10a) both of which are well under 1C so will be gentle on the packs. The big 2400w charger is just for the occasional fast recharge or as a charging station for doing multiple bikes at once. Like yesterday on the Sydney group ride, all the the bikes built by me run on 18S so I could have recharged all 3 of our bikes while stopped for lunch.

Nice work Hyena.

I think this bike is arguably the number 1 hub powered ebike on the forum (in my opinion )

Thanks mate, that's quite a compliment from someone with 2 very sweet custom stealths himself
And thanks Rix and Cruzxia for the compliments too.

WOW!! Your fighter is Awsome! That thing looks wicked with the vented hub and the zock forks. 7KW with 18s. I am guessing between 90 and 100 amps. Got Torque?

Yep running around 100 amp limit. Being a fairly high speed wind it doesn't have a mountain of torque off the line, which is kind of good in a way as you don't have to worry about it flipping you off the back if you lean on the throttle too hard. But if you want to wheelie it a sharp jab of full throttle will do it. The triple clamp forks actually make for quite a heavy front end. I built a bike for a bloke recently with a giant reign xo and it was stupidly light - I could literally lift it with 2 fingers. It had a fox shock and carbon rims and spokes and just steering the bike around my workshop by the bars made it pull up in the air a few times. Crazy. Whacking a big H40 motor and 15ah of 18S lipo on there cured it's anorexia but I can only imagine what it'd be like with a light weight RC drive set up.

[Rix]

Hyena,

Here is a pick of me going 56MPH (92.7 KMH) on the bomber. Slight downhill 2%, but if I factor in my coworker's radar cosign effect of the 2% grade, I am actually going 58MPH (96.3 KMH). This is an old ashphalt road. It was so rough in places that my vision was blurred from bouncing all over the place. YAH!!!! My max draw was 5.1 KW and pedaling my ass off. Not bad for a stock bomber @ 84 Volts with the CA set at 66 AH.

Kepler,

I straightend the post out almost completely and followed your suggestion of snugging the axel nuts and the post nuts in stages finishing with torquing the nuts to 50NM. I think there is a tiny stress crack in the weld from straightening, but its structually sound and I will reweld when I go up north to see my dad. Anyway I tested the bike's accel and regen (low speed and high speed) on this shitty bumpy road that I took the speed run picture on. The nuts did not move or loosen at all. If you look at this pic and compare it the pic I posted a couple of days ago, you can see that the axel post plate even fits better into the grooves now. BTW, I added a jam nut to the axel post. I believe between straightening the post and snugging the nuts in stages like you suggested solved my axel nut problems. Thank you for the advise. Next on the agenda will be venting the hub. I ride smart, but I noticed that when the hub is hot to the touch and I am accelerating, my CA indicates that my current doesn't drop like it does when its cool which I believe I'm loosing some power to heat. Is this correct?

Rix

[QMS]

Hyena,

Here is a pick of me going 56MPH (92.7 KMH) on the bomber. Slight downhill 2%, but if I factor in my coworker's radar cosign effect of the 2% grade, I am actually going 58MPH (96.3 KMH). This is an old ashphalt road. It was so rough in places that my vision was blurred from bouncing all over the place. YAH!!!! My max draw was 5.1 KW and pedaling my ass off. Not bad for a stock bomber @ 84 Volts with the CA set at 66 AH.

Kepler,

I straightend the post out almost completely and followed your suggestion of snugging the axel nuts and the post nuts in stages finishing with torquing the nuts to 50NM. I think there is a tiny stress crack in the weld from straightening, but its structually sound and I will reweld when I go up north to see my dad. Anyway I tested the bike's accel and regen (low speed and high speed) on this shitty bumpy road that I took the speed run picture on. The nuts did not move or loosen at all. If you look at this pic and compare it the pic I posted a couple of days ago, you can see that the axel post plate even fits better into the grooves now. BTW, I added a jam nut to the axel post. I believe between straightening the post and snugging the nuts in stages like you suggested solved my axel nut problems. Thank you for the advise. Next on the agenda will be venting the hub. I ride smart, but I noticed that when the hub is hot to the touch and I am accelerating, my CA indicates that my current doesn't drop like it does when its cool which I believe I'm loosing some power to heat. Is this correct?

Rix

Hey Rix that speed is pretty damn inpressive I recken you have a bit of a freak bike there! Can you confirm those volts and AH figures they dont sound quite right



Hyena. SWEEEEEET Fighter MAAAN. Awsome job mate Had a chat with a Bomber owner over here today is a customer of yours from about 12 months ago, goin to catch up with him for a blast soon

[Rix]

QMS,

Here is a pic of my CA hot off the charger, it actually was at 86.4 volts but settled at 86.1. After I get on the gas for a about 10 seconds, the volts drop to 84 for a bit and then to 80.1. After I use about 230 watts, the volts drop and stay at 78.9-79.1 under no load for the remainder of the cycle. Even when I have used 1330 watts or about 16 AH, the volts read 78.9 with no load. On the gas it drops to about 72 volts though. I am actually thinking of increasing my LVC to 71 volts. When I drain the battery down to less than 20%, its still not getting near the 70 volt LVC like it should. When I originally cut my wattage limiter wire on the CA, the CA settings defaulted to 2055 wheel, 70LVC, and 66 Amps. Haven't touch it. I know I can change this. In fact, I was thinking of dropping the amps to 60 or 55. But I ride the bike smart and like the power. I am going to vent the hub. Just don't like wasted current turning to heat. Just got wait to go see my dad because his shop has everything I need including his knowledge for the shunt mod and speed controller reprogramming.

On another note, does anybody know anything about DNM's DH dual crown MTB Fork? I went to their site because I am really impressed with the Bomber's rear suspension. The rear suspension is so good that I have to actually down set shock to work with the RST One. DNM emailed me and said the fork would cost 530 USD delivered to the states. If their front forks work as good as the rear shock, I wouldn't hesitate buying it. The only downside is the fork is listed as weighing 4.5 kg which tells me that it may have some type of open bath designe and the weight is from the fork oil. Maybe I am wrong. Anyway if anyone has any experience with the DNM Fork, please let me know.

Rix

[cruzxia]

Interesting to know your default CA settings, my Bomber came set as follows:
LVC 69v and 65 amps. If I let the battery settle for a few hours after charging it drops to 80.1v.

After riding you should take a look at the following readings on the CA
Vmin and Amax, that will tell you how low you voltage dropped, and the max current, the two usually happen at the same time, unless the voltage goes below the LVC.
I find that once I have used about 1400wh if I accelerate hard the voltage will dip down to 70v (my new LVC setting) then the output limits to around 3800w. With the LVC set at 70v the Vmin goes as low as 68v, with LVC at 69v the Vmin will drop to 66v
It is because my CA takes a few seconds to react and limit the voltage. I altered some of the advanced settings in the CA and it improved slightly.
If I limit the current in the CA the reaction delay is very noticeable, It accelerates at full for power for a few seconds, and then shuts off the power back to the setting.

Re the forks, I have read plenty of reviews, trying to work out which fork to upgrade to. The Fox 40 forks get great reviews for the way the work, but they need constant rebuilding (service every 10 - 15 hrs), so they are out. The Mazocchi 888 RC3 is the way to go, they get great reviews for function, and everyone says they need almost no maintenance (service every 2 years) They weigh about 3.3kg, and I have seen them for around $850 in the US. The Mazocchi 888 TI comes in at 2.9kg, but it is not worth the extra $700 to save 400g, when your bike weighs 53kg

[Paul_G]

Friday Only MC rack sale...act quick....great for a Bomber

http://www.harborfreight.com/itc-deals.html

must be a member but its worth it for the fantastic prices for a year
29 a year and you get a 10$ gift card

http://images.harborfreight.com/hftweb/ ... ges/20.jpg

[remf]

The Fox 40 forks get great reviews for the way the work, but they need constant rebuilding (service every 10 - 15 hrs), so they are out.

They really are nice forks. They need an oil change every 30 hours - that's easy. The damper rebuild is not so easy but only needs to be done every 100 hours. I think it'd be considerably longer if you're not smashing it constantly. Marzocchi 888's are just as good but they need oil changes & rebuilds too, it's just that they just don't stipulate intervals like Fox. I think they'd need the same servicing as the 40 if you're landing big drops. Open bath vs Closed bath...it really doesn't matter as long as you keep the oil clean.

[QMS]

Interesting to know your default CA settings, my Bomber came set as follows:
LVC 69v and 65 amps. If I let the battery settle for a few hours after charging it drops to 80.1v.

After riding you should take a look at the following readings on the CA
Vmin and Amax, that will tell you how low you voltage dropped, and the max current, the two usually happen at the same time, unless the voltage goes below the LVC.
I find that once I have used about 1400wh if I accelerate hard the voltage will dip down to 70v (my new LVC setting) then the output limits to around 3800w. With the LVC set at 70v the Vmin goes as low as 68v, with LVC at 69v the Vmin will drop to 66v
It is because my CA takes a few seconds to react and limit the voltage. I altered some of the advanced settings in the CA and it improved slightly.
If I limit the current in the CA the reaction delay is very noticeable, It accelerates at full for power for a few seconds, and then shuts off the power back to the setting.

Re the forks, I have read plenty of reviews, trying to work out which fork to upgrade to. The Fox 40 forks get great reviews for the way the work, but they need constant rebuilding (service every 10 - 15 hrs), so they are out. The Mazocchi 888 RC3 is the way to go, they get great reviews for function, and everyone says they need almost no maintenance (service every 2 years) They weigh about 3.3kg, and I have seen them for around $850 in the US. The Mazocchi 888 TI comes in at 2.9kg, but it is not worth the extra $700 to save 400g, when your bike weighs 53kg

Hey cruzxia, my settings and results are pretty much identical to yours How many KM'S have you clocked up on your Bomber so far? I agree re the DNM v the Maz's. I have used heaps of different forks and these are effing awesome Great range of adjustment,really plush ride over 'serious' bumps, super strong with 3rd crown(which the DNM's don't have) and really positive rider feedback


Rix, just wanted to check that AH reading you quoted 66AH didn't seem right You might want to check your wheel circumference setting in the CA also. I changed mine to 2020mm when i fitted the Hook Worms to mine! The factory setting was about 2080mm(i think) This will affect the accuracy of the speedo. Oh and just wondering also was that radar speed check done from a "cruiser"