Changed Cassette, Not Happy

[MarkF]

Hi Everyone

I have a Raleigh Retroglide with a 12 to 32 cassette.It tops out at 21 mph while pedaling as fast as I can. I had my bike shop put a 11 to 34 cassette to give me a little more top end. The problem is when I get to the motor cutout of 19 mph, I can't pedal it any faster. It feels like a hit a wall and the motor is just holding me back. It did do this before but not as bad. I could still pedal past the cut off but ran out of gearing to go faster than 21 mph. Is there something the bike shop might have done inadvertently ?

 

[PaD]

Hi Everyone

I have a Raleigh Retroglide with a 12 to 32 cassette.It tops out at 21 mph while pedaling as fast as I can. I had my bike shop put a 11 to 34 cassette to give me a little more top end. The problem is when I get to the motor cutout of 19 mph, I can't pedal it any faster. It feels like a hit a wall and the motor is just holding me back. It did do this before but not as bad. I could still pedal past the cut off but ran out of gearing to go faster than 21 mph. Is there something the bike shop might have done inadvertently ?

Your new top gear is about 8 - 9% taller and probably equally ”heavier” to pedal.
If you’re using a higher level of assist to reach top speed the sudden ”loss” of assist is a surprising experience.

 

[indianajo]

Mid-drive motors do hold you back above the top speed if the controller has a limit. The only one I've heard has a freewheel, a one way clutch that allows you to pedal, is the yamaha. I bought a geared hub drive for this reason; I want to ride unpowered unless the wind is too high or I'm going more than 30 miles. Direct drive hub also drags when the power cuts off, about one sprocket level in the case of mine.

 

[AZOldTech]

Hi Everyone

I have a Raleigh Retroglide with a 12 to 32 cassette.It tops out at 21 mph while pedaling as fast as I can. I had my bike shop put a 11 to 34 cassette to give me a little more top end. The problem is when I get to the motor cutout of 19 mph, I can't pedal it any faster. It feels like a hit a wall and the motor is just holding me back. It did do this before but not as bad. I could still pedal past the cut off but ran out of gearing to go faster than 21 mph. Is there something the bike shop might have done inadvertently ?

What's the chainring you are using with that cassette??? A 11-34 or 12-32 would barely make a dent at the top speed. But going from a 44T to a 52T chainring would hit the afterburners if you have the legs. Even without changing the cassette from a 12-32 to a 11-34. So what chainring do you have?

 

[MarkF]

The chain ring is a 48 which I left alone. My bike shop called Raleigh to get me a little more top end when I pedal and this was there suggestion. And their cassette. It always had a drop off at 20 mph but I could pedal to 22 pretty easy. Now when i get to 20 I can stand on the pedals with all my strength and can't get it past 20. It just feels like there is more drag now that there was before. I even tried it in 6th gear which is what I had before and it doesn't like me to pedal past 20 mph.

 

[PaD]

The chain ring is a 48 which I left alone. My bike shop called Raleigh to get me a little more top end when I pedal and this was there suggestion. And their cassette. It always had a drop off at 20 mph but I could pedal to 22 pretty easy. Now when i get to 20 I can stand on the pedals with all my strength and can't get it past 20. It just feels like there is more drag now that there was before. I even tried it in 6th gear which is what I had before and it doesn't like me to pedal past 20 mph.

More spinach could be the solution
I still don’t think something has gone wrong with your new cassette. It’s just that with the slightly taller gearing you reach your (present) limit.
There are varying opinions on the resistance from the motor on different bikes but that’s another discussion.

 

[AZOldTech]

The chain ring is a 48 which I left alone. My bike shop called Raleigh to get me a little more top end when I pedal and this was there suggestion. And their cassette. It always had a drop off at 20 mph but I could pedal to 22 pretty easy. Now when i get to 20 I can stand on the pedals with all my strength and can't get it past 20. It just feels like there is more drag now that there was before. I even tried it in 6th gear which is what I had before and it doesn't like me to pedal past 20 mph.

Using this gear calculator, at 80 RPM (which is quite easy to do) with the 12T cog and 48T chainring you should be doing 26.4 mph.
With a 11T cog that gets bumped to 28.8mph. So definitely something else (drag, friction etc..) is keeping you from getting over 20mph. Make sure your wheels spin as freely as before (with disc brakes make sure there is absolutely no rubbing and your brakes are set correctly. Same with your motor contact and/or freewheel.
http://www.gear-calculator.com/

 

[Nova Haibike]

Using this gear calculator, at 80 RPM (which is quite easy to do) with the 12T cog and 48T chainring you should be doing 26.4 mph.
With a 11T cog that gets bumped to 28.8mph. So definitely something else (drag, friction etc..) is keeping you from getting over 20mph.

The factory preset 20 mph cutoff is what is preventing him from going faster. I'd guess that because the cadence is slower, it is more difficult to transition from assisted to non-assisted.

 

[Trail Cruiser]

The factory preset 20 mph cutoff is what is preventing him from going faster. I'd guess that because the cadence is slower, it is more difficult to transition from assisted to non-assisted.

If you don't want the assist to cut off at 20 mph, you might consider a simple trick by fooling the speed sensor.

https://www.ebiketuning.com/e-bike-tuning/badass-box.html

 

[AZOldTech]

The factory preset 20 mph cutoff is what is preventing him from going faster. I'd guess that because the cadence is slower, it is more difficult to transition from assisted to non-assisted.

But I thought he said he was spinning like crazy so I assumed cadence of at least 80 (which isn't spinning like crazy). So cutoff or not that bike with cadence of 80 should be going much faster than 20mph, right? Maybe I should have asked about the precise cadence. Maybe 80, is too much for some people and 60 maybe much easier with a 11T cog. I ride my regular road bike most of the time on a 12T or 11T cog with 50T chainring and 85RPM, so probably my assumption was wrong...

 

[MarkF]

Yes I was spinning very fast with stock set up in 7th gear and would max out at 22 mph. I wanted to be able to hit 25 or better for crossing intersections so I wanted a smaller top gear. I went from a 12 to an 11 and I can tell it doesn't spin as fast at top speed but man I just can't push it past 20. I guess the cutoff was less noticeable on stock set up. I did check my breaks and wheel spins freely.
That tuning box looks interesting but I have the transx system and it doesn't list my motor. They also don't ship to the USA and I live in Las Vegas.

 

[Trail Cruiser]

Yes I was spinning very fast with stock set up in 7th gear and would max out at 22 mph. I wanted to be able to hit 25 or better for crossing intersections so I wanted a smaller top gear. I went from a 12 to an 11 and I can tell it doesn't spin as fast at top speed but man I just can't push it past 20. I guess the cutoff was less noticeable on stock set up. I did check my breaks and wheel spins freely.
That tuning box looks interesting but I have the transx system and it doesn't list my motor. They also don't ship to the USA and I live in Las Vegas.

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You need to have a cadence meter so you can accurately describe what spinning too fast is to you and what comfortable cadence is for you. On, my ebike if I want to maintain higher speed, I use the 9th gear of my 10 speed ebike since the 10th gear gives me a slower cadence (of less than 80 rpm) and my speed is bogged down.

You can convert a cheap speedometer into a cadence meter.

 

[rich c]

I wanted to be able to hit 25 or better for crossing intersections so I wanted a smaller top gear.

You want to go 25mph or better going across intersections? I just can't visualize that.

 

[AZOldTech]

You want to go 25mph or better going across intersections? I just can't visualize that.

I assume he means that when he sees a yellow light he wants to gun it to cross the intersection before it turns red. But here I go making assumptions again...

 

[rich c]

I assume he means that when he sees a yellow light he wants to gun it to cross the intersection before it turns red. But here I go making assumptions again...

Oh, that's a possibility. It would take a good motorcycle to accelerated from stopped to 25mph in the width of the intersection. That's where my mind was going. I rarely race across to beat a red light. It might put me into a competition with a turning car attempting the same maneuver.

 

[MarkF]

Yes when trying to beat a yellow light. Who would expect to go from 0 to 25 across an intersection?

 

[MarkF]

When I say pedaling fast I mean like being in 2rd gear and topping out at 10 mph. My legs can only go so fast and i'm in reasonable health and stamina. When I drop down to 6th gear i have the same ratio as before but I still can't get to 22 like I did before. I talked to the bike shop and they said to bring it in to see if they can see something that could be causing it. I guess another way to put would be like it feels like the brakes are helping to slow me down but I know that's not the case.

 

[AZOldTech]

When I say pedaling fast I mean like being in 2rd gear and topping out at 10 mph. My legs can only go so fast and i'm in reasonable health and stamina. When I drop down to 6th gear i have the same ratio as before but I still can't get to 22 like I did before. I talked to the bike shop and they said to bring it in to see if they can see something that could be causing it. I guess another way to put would be like it feels like the brakes are helping to slow me down but I know that's not the case.

See last message on this thread: https://electricbikereview.com/foru...limit-of-20-miles-hr.12573/page-3#post-168882
It seems like if your bike is rated for max speed 20mph (class 2), no chainring or cog combination could make it go 25mph or higher as the geared hub motor is acting like similar to an engine break. You need a max speed rated bike of 28mph (class 3) to do that (like a CrossCurrent S/X juiced bike or other 28mph Class 3 bikes).

 

[rich c]

Yes when trying to beat a yellow light. Who would expect to go from 0 to 25 across an intersection?

As I mentioned, trying to beat a yellow light isn't a consideration for me either, hence my confusion.

 

[MarkF]

Your bike has a hub motor and mine has a mid drive. I could pedal past the 20mph cutoff on mine to 22 but ran out of gearing to go faster. I wanted to be able to pedal to 25 or close to it anyways but needed a taller, or is it smaller gear to get there. But I suddenly hit a wall that wasn't there before I changed the cassette.