Rear Q100 on 130 mm dropout

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stiaga   100 µW

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Rear Q100 on 130 mm dropout

Post by stiaga » Aug 22 2018 7:49am

Dear all,
I have a road bike and I would like to install a Cute Q100 on the rear wheel but unfortunately the dropout of the road bike is only 130 mm and the Q100 is 135mm...

Surfing on the web I have read that the rear Q100 has some thicknesses that I can polish in order to gain 4/5 mm, but I have some questions about it:
1) Are the thicknesses on the right and on left side hat I can remove and polish?
If yes I could polish 2,5 mm on each side and it should work, but if they are only on the right side (where the sprockets are) what about the alignment of the wheel with the frame?
2) How many sprockets could I use? I guess that more sprockets the pack has and more larger it is, is it correct?

Anyone of you have experience?

Thanks,
Fausto.

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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Aug 25 2018 9:40am

Anyone?

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motomech   1 GW

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Re: Rear Q100 on 130 mm dropout

Post by motomech » Aug 25 2018 11:32pm

stiaga wrote:
Aug 22 2018 7:49am
Dear all,
I have a road bike and I would like to install a Cute Q100 on the rear wheel but unfortunately the dropout of the road bike is only 130 mm and the Q100 is 135mm...

Surfing on the web I have read that the rear Q100 has some thicknesses that I can polish in order to gain 4/5 mm, but I have some questions about it:
1) Are the thicknesses on the right and on left side hat I can remove and polish?
If yes I could polish 2,5 mm on each side and it should work, but if they are only on the right side (where the sprockets are) what about the alignment of the wheel with the frame?
2) How many sprockets could I use? I guess that more sprockets the pack has and more larger it is, is it correct?

Anyone of you have experience?

Thanks,
Fausto.
I suspect most of us are confused by your question, especially the reference to "polish". In English, the verb polish means "to make shinny(bright)", not "to remove material".
Also, you have not specified which version of the Q100 you want to install, the free-wheel version, or the cassette version(C).
I will briefly describe installing both:
Free wheel Q100 (standard or "H")
With a 7-gear free-wheel, installation width is 133 m/m to 134 m/m.
With an 8-gear free-wheel, installation width is 134 m/m to 135 m/m
With a 9-gear free wheel, installation width is 135 m/m to 136 m/m.
Most bikes(steel or alum.), even w/ 130 m/m drop-outs, will accept the above combos, by simply "spreading" the chainstays, especially w/ the 7-gear clusters. People have installed up to 145 m/m motors(not Q100) into 135 m/m dropouts this way with no problems.
The cassette version has installation widths which are about the same, but if you want to try to make either one more narrow, each is a different approach.
With a free-wheel, the only way to make the total width more narrow is to remove one or more gears from the free-wheel, in effect making a custom gear-set(Sheldonbrowm.com talks about this). But, most people would use a DNP Enoch 11T-25T free-wheel to get the small 11 T sprocket. The DNP does not come apart.
With the Cassette, there is a way to remove up to 6 m/m total width by cutting off the "tip"(end) of the spline(The part the cassette slides onto) and, again, making a custom, more narrow cassette.
Tell me what you have and I can give more details.
But again, I would ask a friend to help you, each of you pulling out chain-stay out and try to drop the motor in.
Any way you do it, you will probably have to add at least one flat washer between the cassette/free-wheel and the inside of the drop-out so they will not rub together.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

stiaga   100 µW

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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Sep 07 2018 2:26pm

motomech wrote:
Aug 25 2018 11:32pm
stiaga wrote:
Aug 22 2018 7:49am
Dear all,
I have a road bike and I would like to install a Cute Q100 on the rear wheel but unfortunately the dropout of the road bike is only 130 mm and the Q100 is 135mm...

Surfing on the web I have read that the rear Q100 has some thicknesses that I can polish in order to gain 4/5 mm, but I have some questions about it:
1) Are the thicknesses on the right and on left side hat I can remove and polish?
If yes I could polish 2,5 mm on each side and it should work, but if they are only on the right side (where the sprockets are) what about the alignment of the wheel with the frame?
2) How many sprockets could I use? I guess that more sprockets the pack has and more larger it is, is it correct?

Anyone of you have experience?

Thanks,
Fausto.
I suspect most of us are confused by your question, especially the reference to "polish". In English, the verb polish means "to make shinny(bright)", not "to remove material".
Also, you have not specified which version of the Q100 you want to install, the free-wheel version, or the cassette version(C).
I will briefly describe installing both:
Free wheel Q100 (standard or "H")
With a 7-gear free-wheel, installation width is 133 m/m to 134 m/m.
With an 8-gear free-wheel, installation width is 134 m/m to 135 m/m
With a 9-gear free wheel, installation width is 135 m/m to 136 m/m.
Most bikes(steel or alum.), even w/ 130 m/m drop-outs, will accept the above combos, by simply "spreading" the chainstays, especially w/ the 7-gear clusters. People have installed up to 145 m/m motors(not Q100) into 135 m/m dropouts this way with no problems.
The cassette version has installation widths which are about the same, but if you want to try to make either one more narrow, each is a different approach.
With a free-wheel, the only way to make the total width more narrow is to remove one or more gears from the free-wheel, in effect making a custom gear-set(Sheldonbrowm.com talks about this). But, most people would use a DNP Enoch 11T-25T free-wheel to get the small 11 T sprocket. The DNP does not come apart.
With the Cassette, there is a way to remove up to 6 m/m total width by cutting off the "tip"(end) of the spline(The part the cassette slides onto) and, again, making a custom, more narrow cassette.
Tell me what you have and I can give more details.
But again, I would ask a friend to help you, each of you pulling out chain-stay out and try to drop the motor in.
Any way you do it, you will probably have to add at least one flat washer between the cassette/free-wheel and the inside of the drop-out so they will not rub together.
Sorry for the delay but I didn't receive the mail notification about your post.

Yes, with polish I mean remove material but as far as I understand it isn't needed.
I have to decide which motor install, what do you suggest for a road bike? I have now a freewheel sprocket, could I install a motor with cassette? (Obviously changing the freewheel with a cassette too).

My first idea was to install a cute q100 normal version (not "H").

So according your explanation if I install a six speed freewheel I should have 132/133 mm, is it right?

The bike frame is aluminum, are you sure extending it about 3/4 mm it is safe?

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Re: Rear Q100 on 130 mm dropout

Post by zro-1 » Sep 08 2018 10:27am

The cog side of the freewheel Q100's shaft has a nut and 2 spacers. I had a freewheel version of the Q100 installed in my single speed bike that had 120mm dropout width. You can probably just remove the nut, and get the 5mm you need. Alternatively, you can try replacing one or both of the spacers with washers, or cutting one of the spacers down to the width you need.
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stiaga   100 µW

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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Sep 08 2018 10:45am

zro-1 wrote:
Sep 08 2018 10:27am
The cog side of the freewheel Q100's shaft has a nut and 2 spacers. I had a freewheel version of the Q100 installed in my single speed bike that had 120mm dropout width. You can probably just remove the nut, and get the 5mm you need. Alternatively, you can try replacing one or both of the spacers with washers, or cutting one of the spacers down to the width you need.
And what about the other side where isn't the cog? Are there some spacers or something like that? I'm asking that because if I recover space on only one side I guess I will have problems with chain line.

Do you remember?

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Re: Rear Q100 on 130 mm dropout

Post by docw009 » Sep 08 2018 11:29am

Here's my Q100 and yes, the freewheel side has spacers/nuts. If you are able to fit a narrower gearset, you should get your 5mm.

On the other side, you cannot do anything, unless you are willing to rethread the axle and then you're a better machinist than me.
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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Sep 08 2018 4:51pm

docw009 wrote:
Sep 08 2018 11:29am
Here's my Q100 and yes, the freewheel side has spacers/nuts. If you are able to fit a narrower gearset, you should get your 5mm.

On the other side, you cannot do anything, unless you are willing to rethread the axle and then you're a better machinist than me.
Does this bike have a 130mm dropout?
Could you post a picture of side cog too?

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Re: Rear Q100 on 130 mm dropout

Post by docw009 » Sep 09 2018 2:42pm

135mm. Close up of freewheel base on a larger Q128. The diamaters of a Q100 is smaller than the big gear on most freewheels.
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Re: Rear Q100 on 130 mm dropout

Post by motomech » Sep 09 2018 6:08pm

I think you are worrying too much about "squeezing" the motor in the drop-outs when that is not really the issue(s).
Considerations of installing a Q100(or any mini-motor) include;
.
1)Motor speed! The smaller(lower power) the system, the more important this is.
2)Pedal gearing(sprocket sizes).
3)Wheel dishing(The amount of offset when building the wheel to center the rim.)
.
To address these;
.
1)The Q100H is offered in three speed ranges. They are;
.
Low-speed range, the "201", that is 201 rpm @ 36 Volts. In general, this motor will provide a top speed of 20 mph when installed in a 26" wheel and powered by a 48 Volt system. While many of us consider this a little slow for an Ebike, it is the mini-motor to use when "moderate" hills are to be encountered. It is also good for larger wheels(27.5, 700 cc, 29"). Going to a 52 Volt system can add a couple of mph, to bring the top speed up to a "more fun" 22 mph(in 26" whl.).
.
Mid-speed range, the "260". This is the best motor speed for 90% of Ebike riders. In a 26" whl., it provides a 22 to 23 mph top speed on 48 Volts, while still providing decent hill climbing ability.
.
High-speed motor, the "328". While the difference between the 201 and 260 is not great, it is a big "jump" to the 328. This motor should only be used in 24" or smaller wheels or by very strong cyclists that will not be climbing steeper hills. Mis-matching this speed motor can cause controller over-heating problems and melted wires. Generally, to assume this motor can be used in a "big wheel" and have a "faster" Ebike is a mistake.
.
The Q100 C (CST) is unfortunately, is available in only two speed ranges, the 201 and the 328.
.
2)On almost all Ebikes, pedal gearing means an 11T small gear on the free wheel/cassette and the largest chain ring that will fit on the front. My bikes, w/ a 11T X 48T and a 11T X 50T provides top pedal speeds of 20 mph and 23 mph respectively. This is important to the rider that wants to add with his legs, whether he uses the PAS or cruise control. In general, having enough "pedal gear" to add a mph or two "on top" of the ebike's top speed is the best way to do it.
An 11T sm. sprocket on a cassette is not a problem, as even inexpensive cassettes are available this way. For a free wheel, this means only one thing, The Enoch DNP free whl.
The DNP free wheel is not a favorite of many here. It is heavy and the early ones were noisey. The most recent one I am using is quiet and smooth and the biggest problem I have with the DNP's is that when the 11T gear wears out, the entire free whl. must be replaced and they are not cheap.
.
3)Wheel dishing-This mostly applies to the Q100C . To make room for the long spline that mounts a cassette, the motor core is pushed over to one side. Therefore, the spokes must be adjusted in a such a way that the rim is offset. I have found that the amount depends on the bike. One of my bikes required only a small offset, while the other required quite a bit, to the point I gave up. So it's hard to say if this will be an issue or not.
.
So you see, the "C" version has a couple of things going against it. I understand why many prefer the cassette to the free wheel(it's easier to remove for one thing). But the DNP works well enough that for most, the advantage of using a 260 motor outweighs losing the cassette.
.
A note on the number of gears; One thing new ebike builders don't understand is, once the bike has a motor, very few gears are used. It will stay on the big chain ring all the time and only several gears on the cassette/free whl. are needed. On my low-power " assist" bike, I only use 2, or sometimes 3 gears. On my higher-powered 2 whl. Drive, I stay in the same gear(the 11 T) all the time. People say more gears might be needed if the motor system fails, but the only thing that made me walk(in 8 years), is a flat tire, so I can't comment on that.
.
THE BIG FIX-There is way to avoid all the possible issues listed above, a front motor install. If the forks are steel or alloy and the motor power is kept below 1000 Watts(Volts X Amps), this can work quite well.
.
A final note; I am not a bicycle expert, but I assume your bike with a free wheel and a 130 mm rear drop-out width is an older model, which likely has rim brakes. You need to ask yourself, "does this bike have qualities to make you want to convert it to an Ebike". Rim brakes can work well, but things like disc brakes and a frt. suspension fork can be desirable, especially if you plan to have a top speed above 20 mph.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Sep 10 2018 3:42pm

Actually I have a front Q100 260rpm on my road bike, and I'm considering to move the motor on the rear because I'm not so comfortable thinking that if the fork brakes I will lose all my teeth... :-)

Yes, 260 RPM is the right for me, so Q100h is the right choice for me (Q100 rear 260rpm doesn't exist)

As far as I understood the dimensions are the same with the Q100 normal version, but what about weight of the H version?

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Re: Rear Q100 on 130 mm dropout

Post by docw009 » Sep 10 2018 4:00pm

My scales indicate 4.8 pounds or 2.2 Kg for a Q100H.

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Re: Rear Q100 on 130 mm dropout

Post by stiaga » Sep 10 2018 4:14pm

docw009 wrote:
Sep 10 2018 4:00pm
My scales indicate 4.8 pounds or 2.2 Kg for a Q100H.
So the same weight of the front version.
I'm using it at assist level 1 and it is fine for me, due the fact the H version has more torque I can consider the 328 RPM, what do you think?

Maybe will it need more current reducing the battery life?

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Re: Rear Q100 on 130 mm dropout

Post by motomech » Sep 10 2018 4:17pm

stiaga wrote:
Sep 10 2018 3:42pm
Actually I have a front Q100 260rpm on my road bike, and I'm considering to move the motor on the rear because I'm not so comfortable thinking that if the fork brakes I will lose all my teeth... :-)

Yes, 260 RPM is the right for me, so Q100h is the right choice for me (Q100 rear 260rpm doesn't exist)

As far as I understood the dimensions are the same with the Q100 normal version, but what about weight of the H version?
The Q100H rear IS available in 260(201 and 260). It is the C that is not avail. in 260.
https://bmsbattery.com/ebike-kit/631-q1 ... e-kit.html
So your best bet is the 260H rear w/ a DNP 7-gear free wheel(to get the small 11T sprocket)and "squeeze" it in.
And yes, the standard and H use the exact same motor housing
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

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Re: Rear Q100 on 130 mm dropout

Post by -dg » Sep 11 2018 6:06am

I'm looking at a similar problem, I have a really nice 1984 steel road bike that is 126mm spaced that I want to put a Q100 into.

Spreading a steel frame 3mm is not a big problem but for more than that it is better to cold set the frame and then straighten the dropouts. The issue is that if you just bend the frame, the dropouts are no longer parallel, but the axle faces and nuts are forced to be by the axle. The bend in the stays is not so bad, but forcing the dropouts parallel when you tighten the nuts puts a kink and a lot of stress where the stays join the dropout. This will definitely shorten the life of the frame. I would not attempt to cold set or bend an aluminum frame.

The DNP freewheel has a poor reputation. More importantly, 11 tooth cogs are going to wear fast and be inefficient. 13 teeth is the minimum for good service for cogs. Fortunately for normal bicycle speeds there is no need for very small cogs. On a 700c road bike with 50 teeth in the chainring a 13 tooth rear gets 24.7 mph at 80 rpm cadence. Which is more than fast enough.

So my plan is to use a 6 speed freewheel and experiment with spacers to see if I can keep the spacing under 130. If not, I'll have to re-space the frame to 130ish. Fortunately I have some s speed freewheels in my parts bin. Also, IRD make nice but pricey 5 and 6 speed replicas of the old Shimano 600 freewheels with 13 tooth small cogs.

If I were OP, I"d try really hard not to stretch my aluminum frame. Also, if you have the bike running with a front Q100, check what gears you are actually using. It won't change because of moving the motor to the rear. But, Q100's are not powerful enough to damage front forks. So the best answer is to just ride the bike as is and check the axle nuts are tight from time to time.
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Re: Rear Q100 on 130 mm dropout

Post by motomech » Sep 11 2018 12:07pm

The DNP freewheel has a poor reputation. More importantly, 11 tooth cogs are going to wear fast and be inefficient. 13 teeth is the minimum for good service for cogs.
Early ('10 to '12 or '13) DNP's certainly had some issues, most serious a lack of internal lubricant. By '12, most riders were either injecting grease into them or(as I did w/ my first one)soaking them a bucket of 90 wt. oil before installing them. About that time the manufacturer made several improvements and while it's hard to know what they did, afterward, even the DNP's harshest critics(like neptronic) were admitting they weren't that bad. Grin has been selling them for years, so I guess they think they are ok.
As far as efficiency is concerned, one study (David Wilson's Bicycling Science) calculated for the typical cyclist (inputting approx. 200 Watts), the difference between an 11 T and a 13 T sprocket is in the range of 3 to 4 Watts.
I replaced my early DNP in '14 and it has been quiet and trouble-free since. Since I, like most ebike riders, do not cross chain and in fact shift very little, premature wear on the 11 T has not been a problem and I expect to get to get at least 5000 miles out of this free whl. Given that the price of the DNP has come down about $10 across the range, I can live w/ replacing it every 4 or 5 years.
On a 700c road bike with 50 teeth in the chainring a 13 tooth rear gets 24.7 mph at 80 rpm cadence. Which is more than fast enough.
Not all riders here are top-notch cyclists and 80 rpm is deffinatly getting into the pro range. In fact, the majority of riders here fall into the recreational rider category. Those looking to get some exercise or just cruise the multi-paths, not training for the Tour De France. For those, any compromise made by going to the DNP is more than made up by relaxed pedaling.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

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Re: Rear Q100 on 130 mm dropout

Post by motomech » Sep 11 2018 12:11pm

So my plan is to use a 6 speed freewheel and experiment with spacers to see if I can keep the spacing under 130. If not, I'll have to re-space the frame to 130ish. Fortunately I have some s speed freewheels in my parts bin.
viewtopic.php?f=2&t=27108
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

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Re: Rear Q100 on 130 mm dropout

Post by wturber » Sep 11 2018 11:42pm

motomech wrote:
Sep 11 2018 12:07pm

Not all riders here are top-notch cyclists and 80 rpm is deffinatly getting into the pro range. In fact, the majority of riders here fall into the recreational rider category. Those looking to get some exercise or just cruise the multi-paths, not training for the Tour De France. For those, any compromise made by going to the DNP is more than made up by relaxed pedaling.
FWIW, I've come to the conclusion that I do not like the feel of the 11 tooth cog on my DNP. I can feel the chain seeming to vibrate on it. I assume it's bouncing around the cog more due to the tighter turns each link must make. So I tend to avoid it and spin a bit faster on the 13 gear. I have a 53 tooth chainring on a 26" tire MTN bike. If I had my druthers, I'd swap that 11 tooth for a 12 tooth cog. All that said, the 11 is nice to have. It is just slightly overkill for my needs. If I wanted to be going 30+ all the time, it would be a "must have."
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Re: Rear Q100 on 130 mm dropout

Post by zro-1 » Sep 13 2018 7:23pm

The ideal cadence to motor RPM balance is when you're able to be contributing power through pedaling at top speed. You'll know you're reaching that point because the motor will just be hitting its unloaded max RPM. Be ready to play with cog sizes and chainring sizes to achieve that goal. That perfect balance feels like neither you or the motor are working especially hard to keep the bike at its top speed. On these little hubs you can mostly hear when the motor has reached its unloaded max RPM. It gets quieter, and there's just a hint of an electric hum or whistle, and no real gear noise.

With my single-speed bike I have a 48 tooth chainring and a 16 tooth freewheel. I'm able to hit that cadence/RPM balance on the flats but at a very high cadence (I end up bouncing a bit in the saddle). To fix that I'll be changing my chainring to a 50 or 52 tooth ring. The sacrifice is that I'll need to work a little harder from a stop and going up hills, but the extra little Xiongda in my bike doesn't put out quite as much torque as the Q100H does, so that may not be a concern here. By keeping my pedal effort and the motor's effort balanced then neither are working too hard and getting premature wear or overheating.
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