Hi John, I have just completed my conversion of a ladies MTB to cruzbike using the conversion kit. I did reverse the forks. Now that it is ridable I have encountered a problem with the conversion. I start by rolling, either down a gentle slope or by walking the bike whilst seated to build speed. The bike tracks well and balances well. The balance is maintained whilst I rest my feet on the pedals. However, as soon as I attempt to accelerate the bike by pedaling the steering becomes unstable and the front wheel wants to turn around 180 degrees and I have to fight it using the handlebars. This situation to me is like when the bike is rolling or coasting the front wheel follows the frame because of the very slight rake of the reversed forks. But once power is delivered to the front wheel, the wheel, which is following the frame wants to pull to the front and pull the frame along, hence the front wheel wants to swing around. Has thi s problem been encountered before and what solutions do you propose? Thanks, Wil
Potential instability once pedalling
- Thread starter WilG
- Start date
ak-tux
Zen MBB Master
Hello WilG,
I'am by no means
Hello WilG,
I'am by no means an expert like John, but it seems to me that what you are experiencing is pedal-induced steer. If this is the case, then there is nothing wrong with your bike. This is an expected behaviour of the cruzbike and indeed any other bike similar to the cruzbike i.e. FWD MBB design.
What happens is that once you relax your body begins to adapt and instinctively correct the pedal steer. To achieve this you nedd some time to learn to ride this kind of a bicycle. Please take some time to follow these video instructions by Kim Tolhurst (John's elder brother):
http://www.cruzbiking.com.au/firstride
Spend 30 minutes or so watching the videos and reading the instructions before you go out and try it again.
I'am by no means
Hello WilG,
I'am by no means an expert like John, but it seems to me that what you are experiencing is pedal-induced steer. If this is the case, then there is nothing wrong with your bike. This is an expected behaviour of the cruzbike and indeed any other bike similar to the cruzbike i.e. FWD MBB design.
What happens is that once you relax your body begins to adapt and instinctively correct the pedal steer. To achieve this you nedd some time to learn to ride this kind of a bicycle. Please take some time to follow these video instructions by Kim Tolhurst (John's elder brother):
http://www.cruzbiking.com.au/firstride
Spend 30 minutes or so watching the videos and reading the instructions before you go out and try it again.
Charles.Plager
Recumbent Quant
Hi Wil,
What he (Ak-tux)
Hi Wil,
What he (Ak-tux) said.
In my case, I watched the videos several times before my bike ever arrived and then spent time going through the steps in my driveway.
A couple of other pointers (in addition to what's above which is right):
* Spinning (at a high cadence instead of mashing on the pedals) helps reduce pedal steer.
* It really does get better. I often ride with no hands on the steering at all. Riding with no hands isn't useful in itself, but learning how to ride with no hands helps reduce the pedal steer.
* If things suddenly aren't going well and you feel you're going to fall, take your feet off of the pedals and let your arms take over. Within a couple weeks of practice, you'll find you won't need to do this anymore.
* A lot of us find that attaching our feet to the pedals ( e.g., clipping in, power straps, etc.) helps give us a lot more control over the bike and the steering. Don't do that until you've ridden a while and don't need to pull your feet off of the pedals.
* Not always feasible, but when trying to master this, don't ride other bicycles. Once you've gotten the basics down, it matters a lot less but when you're first going out there, (I believe but have no real scientific evidence that) it helps to only ride this bike.
You can read about my first experiences on one of these bikes here. Good luck and let us know how it goes.
Cheers and welcome!
Charles
What he (Ak-tux)
Hi Wil,
What he (Ak-tux) said.
In my case, I watched the videos several times before my bike ever arrived and then spent time going through the steps in my driveway. A couple of other pointers (in addition to what's above which is right):
* Spinning (at a high cadence instead of mashing on the pedals) helps reduce pedal steer.
* It really does get better. I often ride with no hands on the steering at all. Riding with no hands isn't useful in itself, but learning how to ride with no hands helps reduce the pedal steer.
* If things suddenly aren't going well and you feel you're going to fall, take your feet off of the pedals and let your arms take over. Within a couple weeks of practice, you'll find you won't need to do this anymore.
* A lot of us find that attaching our feet to the pedals ( e.g., clipping in, power straps, etc.) helps give us a lot more control over the bike and the steering. Don't do that until you've ridden a while and don't need to pull your feet off of the pedals.
* Not always feasible, but when trying to master this, don't ride other bicycles. Once you've gotten the basics down, it matters a lot less but when you're first going out there, (I believe but have no real scientific evidence that) it helps to only ride this bike.
You can read about my first experiences on one of these bikes here. Good luck and let us know how it goes.
Cheers and welcome!
Charles
Thanks Guys.
I have been
Thanks Guys.
I have been practicing and have acheved walk to coasting and soft high cadence pedalling. But as soon as I push hard to accelerate or to climb a grade the steering wants to flip around.
I've been thinking about the scrap bike I used on the conversion. It had a rigid curved forward set of forks, the style use on the 90's model frames, where the forks curve forward slightly. Not the straight forks modern MTB's have. The conversion kit instructions said to turn around the forks, so I did that. Which brings me to the rake. On rear wheel drive the frame/fork allows a rake so that the front wheel-to-ground point trails the frame, which assists in natural stability for the bike to track ahead on a straight line, even while coasting without a rider. On the fwd cruzbike, the front wheel-to-ground point tracks behind the frame, as in conventional rear wheel drive, but with the front wheel now pulling the bike along, is it possible that the wheel (when under traction) wants to move ahead of the frame and hence, wants to flip around?
Just a though. Any experience with this problem before I put a lot more hours into "practice"? Should I change the forks to straight?
Thanks, Wil
I have been
Thanks Guys.
I have been practicing and have acheved walk to coasting and soft high cadence pedalling. But as soon as I push hard to accelerate or to climb a grade the steering wants to flip around.
I've been thinking about the scrap bike I used on the conversion. It had a rigid curved forward set of forks, the style use on the 90's model frames, where the forks curve forward slightly. Not the straight forks modern MTB's have. The conversion kit instructions said to turn around the forks, so I did that. Which brings me to the rake. On rear wheel drive the frame/fork allows a rake so that the front wheel-to-ground point trails the frame, which assists in natural stability for the bike to track ahead on a straight line, even while coasting without a rider. On the fwd cruzbike, the front wheel-to-ground point tracks behind the frame, as in conventional rear wheel drive, but with the front wheel now pulling the bike along, is it possible that the wheel (when under traction) wants to move ahead of the frame and hence, wants to flip around?
Just a though. Any experience with this problem before I put a lot more hours into "practice"? Should I change the forks to straight?
Thanks, Wil
Thanks Guys.
I have been
Thanks Guys.
I have been practicing and have acheved walk to coasting and soft high cadence pedalling. But as soon as I push hard to accelerate or to climb a grade the steering wants to flip around.
I've been thinking about the scrap bike I used on the conversion. It had a rigid curved forward set of forks, the style use on the 90's model frames, where the forks curve forward slightly. Not the straight forks modern MTB's have. The conversion kit instructions said to turn around the forks, so I did that. Which brings me to the rake. On rear wheel drive the frame/fork allows a rake so that the front wheel-to-ground point trails the frame, which assists in natural stability for the bike to track ahead on a straight line, even while coasting without a rider. On the fwd cruzbike, the front wheel-to-ground point tracks behind the frame, as in conventional rear wheel drive, but with the front wheel now pulling the bike along, is it possible that the wheel (when under traction) wants to move ahead of the frame and hence, wants to flip around?
Just a though. Any experience with this problem before I put a lot more hours into "practice"? Should I change the forks to straight?
Thanks, Wil
I have been
Thanks Guys.
I have been practicing and have acheved walk to coasting and soft high cadence pedalling. But as soon as I push hard to accelerate or to climb a grade the steering wants to flip around.
I've been thinking about the scrap bike I used on the conversion. It had a rigid curved forward set of forks, the style use on the 90's model frames, where the forks curve forward slightly. Not the straight forks modern MTB's have. The conversion kit instructions said to turn around the forks, so I did that. Which brings me to the rake. On rear wheel drive the frame/fork allows a rake so that the front wheel-to-ground point trails the frame, which assists in natural stability for the bike to track ahead on a straight line, even while coasting without a rider. On the fwd cruzbike, the front wheel-to-ground point tracks behind the frame, as in conventional rear wheel drive, but with the front wheel now pulling the bike along, is it possible that the wheel (when under traction) wants to move ahead of the frame and hence, wants to flip around?
Just a though. Any experience with this problem before I put a lot more hours into "practice"? Should I change the forks to straight?
Thanks, Wil
Charles.Plager
Recumbent Quant
Hi wil,
Why don't you post a
Hi wil,
Why don't you post a few pictures. I would guess the bike is fine (I don't recall seeing a conversion with the fork turned around that wasn't - but I'm not an expert).
Cheers,
Charles
Why don't you post a
Hi wil,
Why don't you post a few pictures. I would guess the bike is fine (I don't recall seeing a conversion with the fork turned around that wasn't - but I'm not an expert).
Cheers,
Charles
John Tolhurst
Zen MBB Master
Interesting thought that
Interesting thought that powering the front wheel might mean a different trail is required. The power applied to the wheel points the wheel far more strongly than trail can do so. There are many dimensions to the riding skill. You'll discover new things for a long while into it. That is the learning curve is initially steep, but then keeps going up at a moderate angle. You near the point of inflection on that curve, perhaps.
Interesting thought that powering the front wheel might mean a different trail is required. The power applied to the wheel points the wheel far more strongly than trail can do so. There are many dimensions to the riding skill. You'll discover new things for a long while into it. That is the learning curve is initially steep, but then keeps going up at a moderate angle. You near the point of inflection on that curve, perhaps.
