Sur-Ron - New Mid drive Bike

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 05 2020 7:40pm

Merlin wrote:
Apr 05 2020 7:37pm
nobody use 18"? ...thats pretty crazy mr. "offroad" -> any stock enduro has 18" on rear ...mx 19" rear..... :confused:
Looks bad ass!

Could you share your rim and tire specs?

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 05 2020 7:58pm

sure...same what i use on lmx =)
except ...surrons rear is 18 x 2.15 vs 18x 1.85(lmx)


sm pro wheels 18/21
CST 755 rear 3.5
metzeler 6 days 80/90/21

(dont know what ES always rotates pictures but iam tired of it to fix)
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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 05 2020 8:04pm

Merlin wrote:
Apr 05 2020 7:58pm
sure...same what i use on lmx =)
except ...surrons rear is 18 x 2.15 vs 18x 1.85(lmx)


sm pro wheels 18/21
CST 755 rear 3.5
metzeler 6 days 80/90/21

(dont know what ES always rotates pictures but iam tired of it to fix)
Thanks! 26" up front?

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 05 2020 8:06pm

nope

metzeler 6 days 80/90/21

equal to 26 x 2.5 in height.

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Re: Sur-Ron - New Mid drive Bike

Post by tolkaNo » Apr 05 2020 8:38pm

Offroader wrote:
Apr 05 2020 3:52pm
The 18x1.6" rim I am using weighs 1309 grams or 2.8lbs.

My 18x1.6" rim
Image
Where did you order that rim from?

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 05 2020 8:47pm

Finding an 18" rim in 1.4" or 1.6". They are very difficult to find. I bought a couple and one 18x1.6 rim was too heavy.

The 18" rims that are easily found and common are all very wide sizes built for heavy dirtbikes. I did not want a heavy rim. I want to keep the rear wheel light weight so not to affect the suspension performance.

The reason the Sur-Ron is so great and the rear suspension works so well is because we don't have a 25lbs hub motors back there. Why would I want to add a 5lbs rim and a 15 lbs tire?

The Sur-Ron suspension is amazing and I'm so happy coming from a hub motor bike. Remember, you guys are putting heavy rims and tires on a rear suspension designed with a bicycle rear shock.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 05 2020 8:56pm

Offroader wrote:
Apr 05 2020 8:47pm
Why would I want to add a 5lbs rim and a 15 lbs tire?
I have no idea where you are getting your numbers - but I don't think they are remotely realistic for what people have been installing.

Funny you are lecturing people about tire weight when you Shinko weighs 7.4 pounds! :lol:

My M403 weighs 5 pounds and I am running tubeless, so your tire weighs close to twice as much as mine. :wink:

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 05 2020 9:22pm

:lol:


stock surron rear with "a" 70/100/19 tire -> 14,1 lbs
18x1.85 Excel with tubliss kit + 18x 3.5 CST -> 15,4 lbs (disc missing in this pic...so add 0.44lbs ...-> 15,9 lbs

Total: 1,8lbs 0,8Kg more for:

...tubliss, no flats, 5-6 psi plush ride, grip as frock everywhere, nice looks

surron rear suspension works so great? ......the 50$ DNM shock? i would replace that crap way earlier before the (DNM) fork.
Its shit on surron and same shit on lmx. its good for hub crap where suspension is just for the look :lol:

the (stock) killah fork is way better than those DNM USD wobble shit.

no offense bro....i think for you + what i know/saw in your rare videos the SR241 fits like a glove for your riding style/terrain.
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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 05 2020 9:49pm

I really need to know the tire weights because the tires you are using seem to be more light weight then what I saw 3.5" tires weighing.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 06 2020 8:52am

Merlin wrote:
Apr 05 2020 9:22pm
:

...tubliss, no flats, 5-6 psi plush ride, grip as frock everywhere, nice looks


no offense bro....i think for you + what i know/saw in your rare videos the SR241 fits like a glove for your riding style/terrain.
I was thinking more about this. First, you are using an 18" tire and I agree you did the smart thing and laced an 18" in the rear. This is the optimal rim size to use for the Sur-Ron. I personally think a 18x1.6" rim is better suited. I even tried to get an 18x1.4" rim, but since the 1.6" rim doesn't weigh much more that is probably a better size to use.



You chose an 3.5"-18" C755 tire. I would have just chosen an 3.00-18". The 3.00-18" is more of a match in tire size to the front.

These are probably not important differences unless the 3.5" tire weighs much more than the 3.00".

But either way I like the shinko 241 tire because it is wears somewhat slowly on pavement, but not too slowly as it has a soft tire compound. I also don't ride in wet, muddy, sand, etc. I do lots of off-road riding but its mostly on dry dirt and grass. The shinko 241 works very well in a lot of conditions and is smooth on pavement.

What I think is a very bad idea is using a 19" 3.5" on the rear, that is just a bad idea and I see it a lot here.

The other smart thing you did was go tubeless. I have to find out if I can do that on my 18x1.6 rim and tire.

I actually just got a snake bite tire tube puncture on my last ride and had to ride my bike home over 2 miles completely flat in the rear tirer on my sur-ron. If I had tubeless I wouldn't have had my ride ended by this. Lucky for me I am able to ride my bike up to 30MPH speeds with the rear tire completely flat and didn't have to push it home.

To sum it up you are basically doing what I am doing, using an 18" tire. That was the smart decision. Going with a 3.5" I can't really say if that was smart or not as I would have to ride with such a large tire. I would have to see how that lifts up the rear of the bike because it is a larger tire than the 19" front. I would have to see how it deals with the chain. I would have to see how quickly that tire wore away the knobs and how hard the tread compound is.

For most people I really believe the optimal tire and rim combo would be a 18x1.6" rim with a shinko 241 18x3.00 tire. This is an almost exact size match to the stock 19" tire. It will not mess with your suspension geometry.

I actually didn't mind the stock 19" on the rear, the big issue with that is it wore away in less than 500 miles. It didn't have the greatest traction as I was always spinning it on the grass and ripping everything up.

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Apr 06 2020 11:56am

stock surron rear with "a" 70/100/19 tire -> 14,1 lbs
Hey Merlin, are you referring to the whole weight of the rear wheel with tire, tube, rim, hub, sprocket and disk? The stock CST tires that come on the SurRon are 4.6 pounds stand alone.

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 06 2020 12:02pm

Hmm..
Arent my pics visible from the wheel on the scale?

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 06 2020 2:00pm

The tire itself, we should document what each tire weighs exactly to get a better idea about what is available.

The Sur-Ron Stock 19" tire weighs: 4lbs 8oz

My Shinko 241 3.00x18" weighs: 7 lbs 4 oz
>
Stock Sur-Ron 19" Tire below
Image


Shinko 241 18x3.00" below
Image

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 06 2020 2:07pm

Just finished building and truing the wheel. This is probably the best and cheapest way to do it properly. Just buy a cheap clamp on dial indicator.

You really only need one clamp on dial indicator because the radial truing can't be done with 12 guage spokes on a motorcycle wheel. The spokes would break before you moved a motorcycle rim radially.

Here is link to what I use for truing all my rims, works well because you can clamp it onto the wheel nuts for a secure and easy fit.
https://www.harborfreight.com/Clamping- ... 63656.html

Image

Image

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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Apr 06 2020 4:37pm

Merlin wrote:
Apr 06 2020 12:02pm
Hmm..
Arent my pics visible from the wheel on the scale?
My work computer doesn't allow the images to load, I will check when I get home tonight.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 06 2020 8:58pm

Offroader wrote:
Apr 06 2020 8:52am
I personally think a 18x1.6" rim is better suited. I even tried to get an 18x1.4" rim, but since the 1.6" rim doesn't weigh much more that is probably a better size to use.
Why on earth is a narrower rim better suited? The more narrow, the more bulbous the profile of the tire will be, which results in less tire intact with the ground. Putting 3.0" tire in a 1.6" rim will make a round profile - not ideal at all.
Offroader wrote:
Apr 06 2020 8:52am
You chose an 3.5"-18" C755 tire. I would have just chosen an 3.00-18". The 3.00-18" is more of a match in tire size to the front.
Why would you prefer having less traction than what fits? What do you mean its more of a match to the front tire? They make front and rear motorcross wheels for a reason - the back is always much wider than the front traditionally.
Offroader wrote:
Apr 06 2020 8:52am
These are probably not important differences unless the 3.5" tire weighs much more than the 3.00".
3.5 / 3.0 = 116%

So if a 3.0" tire weighed 7 pounds, 3.5" would weigh roughly one pound more. Going tubeless shaves that weight off, so a tubeless 3.5" tire could weigh less than your tube 3.0" tire and have significantly more traction.

In any event, do you really think one or two pounds would make any noticeable difference to the suspension? I don't, but the difference in traction would definitely be noticeable.
Offroader wrote:
Apr 06 2020 8:52am
But either way I like the shinko 241 tire because it is wears somewhat slowly on pavement, but not too slowly as it has a soft tire compound. I also don't ride in wet, muddy, sand, etc. I do lots of off-road riding but its mostly on dry dirt and grass. The shinko 241 works very well in a lot of conditions and is smooth on pavement.
What you describe isn't really off-road. I could be wrong, but I think more people ride their Sur Ron under real off-road conditions where knobby tires are much better for the most part (unless you ride primarily on sand).

Offroader wrote:
Apr 06 2020 8:52am
The other smart thing you did was go tubeless. I have to find out if I can do that on my 18x1.6 rim and tire.
I see no reason why you couldn't go tubeless.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 06 2020 9:28pm

I can explain what I am worried about. It is about weight. I need to do more testing but my concerns about weight may have not been unfounded.

I finally got my Sur-Ron tire fully built and installed. While it seems to have better traction, I can tell that when I hit things with the rear, it feels more harsh. This may be because I inflated to 14 PSI, which is the same PSI I inflated my Sur-ROn 19" tire to. It is possible that 14 PSI is too much on the shinko 241 which is causing it to feel harsh.

The weight differences between the Sur-Ron wheel and my 18" build is only 3 lbs.

With the Sur-Ron tire, when I ride over anything fast, the rear feels just as plush as the front, which is amazing. When I ride over stuff now with the Shinko 241, I can feel a more harsh hit in the rear. It isn't a huge difference, but I can tell the tire feels harder.

This is why I need to do more testing. Is the 14PSI too much for the Shinko 241? Is the 3lbs making the rear more harsh? Is it possible I need to retune the rear suspension because of the extra 3 lbs of weight?

Please don't get me wrong, it isn't a huge difference, but it is a noticable difference that I'm not a fan of. Even riding down steps I could have sworn it was much smoother with the Sur-Ron tire.

I will have to do more testing, and then switch my tire over to the Sur-Ron tire to see what is going on after I ride more with my 18".

But this is exactly what I am worried about is weight! 3lbs or 5lbs, makes a huge difference when we have bicycle suspension. The rear shock was not made to handle these heavy rear wheels. I'm concerned right now because I don't want to give up what was so great about the Sur-Ron and what I hated with hub motor bikes. I loved how the Sur-Ron rear suspension felt just as plush as the front fork when riding over stuff.
Last edited by Offroader on Apr 06 2020 9:39pm, edited 2 times in total.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Apr 06 2020 9:31pm

Here are some pics of the 18x3.00 shinko 241 tire. What is great about this 18"x3.00 tire is it is basically a 100% match in size to the stock 19" tire. That means geometry isn't affected as the rear is not adjustable.

You can see the pictures how exact in size it is.

Image

Image

Image

Image

Image

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 06 2020 9:36pm

Offroader wrote:
Apr 06 2020 9:28pm
With the Sur-Ron tire, when I ride over anything fast, the rear feels just as plush as the front, which is amazing. When I ride over stuff now with the Shinko 241, I can feel a more harsh hit in the rear.
How do you know what you are feeling is because of additional weight? Your Shinko has nearly twice the rubber as the stock tire, so maybe it's more stiff? Since it wears less, maybe its not as soft?

Do you really think if you put a 6 pound backpack on that all of the sudden your suspension would suck? (6 pounds would be 3 more pounds on each wheel)

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Apr 06 2020 9:39pm

Offroader wrote:
Apr 06 2020 9:31pm
Here are some pics of the 18x3.00 shinko 241 tire. What is great about this 18"x3.00 tire is it is basically a 100% match in size to the stock 19" tire. That means geometry isn't affected as the rear is not adjustable.
Seems like most folks that are running taller rear wheels also use taller wheel up front. That means more ground clearance and taller people appreciate the gain in height but no real change in geometry. :wink:

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 06 2020 9:51pm

if you have the DNM shock on the rear i dont wonder why it feels like shit :D
is this a dnm shock without sticker? i cant see it on your pics.

14psi for that tire sounds ok to me.

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Apr 07 2020 3:00am

He has the FastAce, wonder which one is better fast or dnm?

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Apr 07 2020 3:37am

Must be Fastace because i cant imagine theres something below dnm :D

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Re: Sur-Ron - New Mid drive Bike

Post by st35326 » Apr 07 2020 5:56am

madin88 wrote:
Mar 03 2020 12:13pm
st35326 wrote:
Mar 03 2020 6:03am
This community has stagnated and shrunk for years, now with the average user on this forum being 54 years of age nobody is doing anything different than they were in the 8 plus year old threads. Motorsports competition is one of the best ways to encourage tech advances and the spread of new ideas.

A lot of you guys use Luke's name as if its a magic spell to automatically win you an argument.

Really?
I think that this youtube guy would not be able to ride with bikes like the Surron without the research work of people like LFP and others with similar interests.
Whether here in ES, YT, FB or somewhere else is not the point, thing is that your statemets are disrespectful and arrogant towards the community.
I would count myself as one of those "research and build guys" most of the time, and have absolut the same respect if not more for folks who doing stunts or cool things when riding, but the best race driver is nothing without mentioned people developing new stuff (like Surron tuning controller and battery), or mechanics which keep his vehicle steady.


Yeah then why don't you even know the name of the Chinese engineers who created the Sur-Ron? Dipship.

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Apr 07 2020 11:54am

Offroader wrote:
Apr 06 2020 9:31pm
Here are some pics of the 18x3.00 shinko 241 tire. What is great about this 18"x3.00 tire is it is basically a 100% match in size to the stock 19" tire. That means geometry isn't affected as the rear is not adjustable.

You can see the pictures how exact in size it is.

Image

That came out really nice. What you need on the front now is a 2.75-19 SR241. Its just taller than the 3.00-18 you got on the rear and will correct the geometry.

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