Sur-Ron - New Mid drive Bike

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Jonathan1981   100 W

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Re: Sur-Ron - New Mid drive Bike

Post by Jonathan1981 » Dec 23 2018 12:40am

StingerRUS wrote:
Dec 21 2018 12:57am
Just got 60 tooth sprocket from lunacycle. I would not put this low quality part on my bike. Very disappointing...
Jist look at the stock sprocket to understand what surface roughness you should see on aftermarket sprockets. ImageImageImage

Sent from my Pixel 3 using Tapatalk
Good for quick prototype project, sure, will do the trick but ultimately an inferior method of manufacturing for that component. Sprockets need to be machined. Laser cutting leaves coned edges, inferior surface details and is dimensional less precise :(

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Dec 23 2018 1:59am

Has anyone had this situation with Luna? I ordered a bike almost 4 weeks ago and they haven't shipped it yet. They told
me their loading dock was broken down and they could only ship on Fridays. It will be over 4 weeks without shipping
the day after Christmas. Does anyone have any data?
luna order.png

artisanstone   10 W

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Re: Sur-Ron - New Mid drive Bike

Post by artisanstone » Dec 23 2018 10:14am

motomoto wrote:
Dec 23 2018 1:59am
Has anyone had this situation with Luna? I ordered a bike almost 4 weeks ago and they haven't shipped it yet. They told
me their loading dock was broken down and they could only ship on Fridays. It will be over 4 weeks without shipping
the day after Christmas. Does anyone have any data?luna order.png
No, but that sucks.

slipperyclock   1 µW

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Re: Sur-Ron - New Mid drive Bike

Post by slipperyclock » Dec 23 2018 11:32am

motomoto wrote:
Dec 23 2018 1:59am
Has anyone had this situation with Luna? I ordered a bike almost 4 weeks ago and they haven't shipped it yet. They told
me their loading dock was broken down and they could only ship on Fridays. It will be over 4 weeks without shipping
the day after Christmas. Does anyone have any data?luna order.png
I had a similar issue, ordered a few weeks ago and did the chat on their site. I was told the same thing. I would recommend you call them. The chat and email responses seem rather cold and generic but when I called, everyone was insanely helpful and friendly. Speaking with them over the phone made it a much better experience. Plus they have no gray instock, they said the next shipment is on the boat from China. It might be in your best interest to pick a different color. But yeah give them a call they are very friendly and accomodating.

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 23 2018 2:09pm

My X-bike got shipped the same day I ordered it. It was super fast.

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Dec 23 2018 2:34pm

I think it's because I am having them ship it to ASI so that they can finalize the tuning and make wiring harnesses so that
we all can have fast bikes. Since it is not Luna, they want to put the brakes on it, especially because it is me doing it.

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Dec 23 2018 3:06pm

I don't know how you guys can want more speed and power. I already feel like the stock suspension, wheels/tires, and swingarm stiffness are barely suffiecient for the speeds I'm hitting on trails znd a trip to the motocross track showed them to be insufficient for the speed this bike can attain on a 100ft straight away. I'm working on the first two but I have no urge to increase power and no one who's ridden mine thought it needed more power. The range is just barely enough for the rides I do. More power is gonna mean less range.

matthepp   1 µW

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Re: Sur-Ron - New Mid drive Bike

Post by matthepp » Dec 23 2018 4:23pm

Thanks guys for the feedback about washing, etc. I have a little ryobi electric power washer. I'm going to continue to use it on all my bikes. I'll hit the ends of the sur ron thoroughly and take it easy through the center section of the bike. I like in the least salty driest possible climate. I'll try to remember to report any failures that arise. I got a better top speed with the green/black wire tied in sport. I'll still need a bigger sprocket for the hills. I am trying the LC 60 tooth since I have it ordered, maybe I'll try to polish down the laser cut profile edges? I got a riser bar on now which is essential for most folks. Now for that bash guard! Motomoto, I recently ordered a blue x bike and it came quick.
I'm sure this sentiment has been covered many times but what has been great already is that this bike is great for lots of folks. I love getting in way over my head on technical moto singletracks. My wife didn't really take to a klx140 but she loves zipping around town showing this off to her girlfriends. Many smiles from stoned friends giving it a whirl at late night xmas parties. Even my 8 yr old has mastered the one leg over the saddle, hop-on-with-a-little-throttle-twist and off he goes. He just can't stop without a spill, Ha.

I'm pondering a few more upgrades of course for trail riding and would love to hear opinions. Has anyone put a 26"xroughly2.6 downhill wheel on the front for better roll? Would the geometry handle the extra resultant rake? Is it worth suspension upgrades? Anyone know where to get heavier springs that'll work in the RST? How bout scavenging used good quality parts from 5 yr old cheap downhill bikes (saints, fox40 Rc2, dhx5.0)? Worth it?
Cheers all and happy holidays, Matt

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » Dec 23 2018 5:10pm

What someone needs to do is make an adapter to mount a commonly available sprocket type such as a kart or pitbike.

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Dec 23 2018 5:56pm

I got a "firm" spring directly from RST by contacting through their website. It's an improvement but I'm waiting to hear if they have an extra firm spring. I still wallow too much on downhills and jump faces and bottom too easily on jump landings.

I also added 20cc of 20 wt oil to the damper leg and 50cc to the spring leg. This definitely helps lubrication and I think it reduced the air volume enough to get some ramp up. Next, I'll open up the damper and either add shims to the compression and rebound pistons or put in thicker oil.

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Dec 23 2018 6:11pm

I've seen so many different replacement tires mentioned but I'm not sure which one fits my criteria. For now I'm staying with stock rims. The rear looks like it has more clearance on the sides than the front. I want the tallest tire on each end that doesn't rub on the sides. I don't mind doing a little trimming so long as I still have side knobs for cornering. The stock tires look wider than they are tall so I want the opposite profile. Reasonable weight and a fast rolling offroad tread are preferred.

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 23 2018 7:56pm

Lelandjt wrote:
Dec 23 2018 3:06pm
I don't know how you guys can want more speed and power. I already feel like the stock suspension, wheels/tires, and swingarm stiffness are barely suffiecient for the speeds I'm hitting on trails znd a trip to the motocross track showed them to be insufficient for the speed this bike can attain on a 100ft straight away. I'm working on the first two but I have no urge to increase power and no one who's ridden mine thought it needed more power. The range is just barely enough for the rides I do. More power is gonna mean less range.
Most guys are probably using it as a motorcycle on the street and want higher top speed and faster acceleration. This is where you can always use more power. I find the bike pretty stable at high speeds on the street. It would be nice if it could quickly accelerate to like 55MPH.

For off-roading the bike, it has probably enough top speed. Where it lacks is acceleration. You can't easily full throttle the bike right before a jump to get more air for example. You also can't lift up the front of the bike easily to do a wheelie.

The bike does have decent power, I think it could use a little bit more though, even for off-roading.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 23 2018 8:02pm

Important question, I notice that many bolts screwed into the aluminum frame are some kind of steel as they are slightly magnetic.

These are the 4 M8 bolts holding the motorcycle seat
The 2 M8 bolts that hold the footpeg/kickstand bracket

Since these bolts look to be screwed directly into the aluminum frame, would it be OK to replace those with aluminum bolts?

I am actually surprised the seat and footpegs are bolted into the aluminum frame as I thought aluminum threads are too weak for stress areas like the seat and the footpegs. This leads me to the other question in that shouldn't the bolts that screw into the aluminum frame be aluminum also for least corrosion issues?

Some other bolts don't make sense, the 2 bolts right below the key switch which screw into the frame are very long M6 bolts that seem to be steel. They don't need to be that long as they just stick out below the frame by like 6mm. Why wouldn't all these bolts holding plastic or brake lines be aluminum as there is no stress at all in these locations?

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Dec 23 2018 9:10pm

I wouldn't recommend aluminum bolts. They break too easily and the threads can easily seize when mated with another aluminum part. Graded steel bolts would probably be the best. Titanium might be another option if cost is no issue. For sure use anti-seize or some kind of grease to keep water out of the threads.

Most of the stock bolts appear to be low grade, chrome plated steel with not a particularly good finish.
"One test is worth a thousand opinions"

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 23 2018 9:19pm

If they are zinc or chrome-plated they should be fine. It's also worth mentioning that galvanic corrosion can only occur with salt present. Not sure how salty it is where you live.

https://www.hunker.com/12502151/screws- ... h-aluminum

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 12:44am

3DTOPO wrote:
Dec 23 2018 9:19pm
If they are zinc or chrome-plated they should be fine. It's also worth mentioning that galvanic corrosion can only occur with salt present. Not sure how salty it is where you live.

https://www.hunker.com/12502151/screws- ... h-aluminum
Yeah thats the thing, I'm driving through a lot of salt water. So much so that I can taste the salt on my face.

I'm putting fenders on so maybe that will cut it down. I'm going to try and not drive when the streets are wet because of this.

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Dec 24 2018 12:53am

On a bike this size, 5 or 10 times the stock power would be great fun.

It's roughly the same size as a big wheel 85cc motocrosser. They have about 20 -25 hp.

Why not have a 40 hp electric the same size?

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 12:55am

Offroader wrote:
Dec 24 2018 12:44am
Yeah thats the thing, I'm driving through a lot of salt water. So much so that I can taste the salt on my face.
In that case, maybe try a couple wraps of teflon tape (thread seal). That should prevent direct contact that would eliminate potential galvanic reactions.

I would try two wraps of teflon tape, put the bolt in and take it out to inspect the tape. If it holds without any holes in the tape, you should be golden.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 1:00am

fechter wrote:
Dec 23 2018 9:10pm
I wouldn't recommend aluminum bolts. They break too easily and the threads can easily seize when mated with another aluminum part. Graded steel bolts would probably be the best. Titanium might be another option if cost is no issue. For sure use anti-seize or some kind of grease to keep water out of the threads.

Most of the stock bolts appear to be low grade, chrome plated steel with not a particularly good finish.
I bought this stuff for an aluminum bottom bracket on a steel frame. It is zinc anti-seize and seems to be recommended for aluminum. Would this stuff work well?

https://www.amazon.com/gp/product/B00JR ... UTF8&psc=1

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 1:03am

motomoto wrote:
Dec 24 2018 12:53am
On a bike this size, 5 or 10 times the stock power would be great fun.

It's roughly the same size as a big wheel 85cc motocrosser. They have about 20 -25 hp.

Why not have a 40 hp electric the same size?
To not break bones and kill me for one. :D

In all seriousness, it would be fun if it accelerated 150%-200% faster, but I don't really have any interest in a bike that lifts the front wheel off the ground without even trying.

Anyhow at 3KW, it the motor puts out 4HP. Since it is geared down 7.6:1, it seems like it is already comparable to a 30HP motor. In that case, 10x more power would be equivalent to 300HP, right? I know gearing down isn't exactly the same as pure HP (since it has to develop RPMs), but the experienced torque would be similar, would it not?

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Dec 24 2018 1:21am

Offroader wrote:
Dec 24 2018 1:00am
I bought this stuff for an aluminum bottom bracket on a steel frame. It is zinc anti-seize and seems to be recommended for aluminum. Would this stuff work well?

https://www.amazon.com/gp/product/B00JR ... UTF8&psc=1
Yes, that should work well. A high salt environment is hard to deal with. Keeping the salt and water away from the threads as much as possible is the best approach.
"One test is worth a thousand opinions"

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 1:31am

fechter wrote:
Dec 24 2018 1:21am
Offroader wrote:
Dec 24 2018 1:00am
I bought this stuff for an aluminum bottom bracket on a steel frame. It is zinc anti-seize and seems to be recommended for aluminum. Would this stuff work well?

https://www.amazon.com/gp/product/B00JR ... UTF8&psc=1
Yes, that should work well. A high salt environment is hard to deal with. Keeping the salt and water away from the threads as much as possible is the best approach.
I'd use both. Brush some of that stuff on the threads then put a couple wraps of teflon tape on.

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Dec 24 2018 2:18am

3DTODO wrote:
In all seriousness, it would be fun if it accelerated 150%-200% faster, but I don't really have any interest in a bike that lifts the front wheel off the ground without even trying.

Anyhow at 3KW, it the motor puts out 4HP. Since it is geared down 7.6:1, it seems like it is already comparable to a 30HP motor. In that case, 10x more power would be equivalent to 300HP, right? I know gearing down isn't exactly the same as pure HP (since it has to develop RPMs), but the experienced torque would be similar, would it not?
In all seriousness, interest in a bike that lifts the front wheel off the ground without even trying is the only thing I live for.

I guess we have different opinions.

And by the way, it's 4 hp at the rear wheel and not multiplied by anything.

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 2:23am

motomoto wrote:
Dec 24 2018 2:18am
3DTODO wrote:
And by the way, it's 4 hp at the rear wheel and not multiplied by anything.
3DTODO? Don't see how that could even be a typo.

Anyhow. So you really think it would have the same torque if it was geared 1:1 as it does geared 7.6:1???

Grantmac   10 kW

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » Dec 24 2018 2:59am

Don't confuse torque and HP. The motor is 3Kw ~4hp, gearing it down by any amount doesn't increase its HP.

I'm with motomoto, I'd be interested in a Sur-Ron if it was +10kw otherwise it's just a heavy ebike without pedals.

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