Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Handcycle traction improvement

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Handcycle traction improvement

Old 06-22-22, 12:00 PM
  #1  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Handcycle traction improvement

Greetings all. I initially posted this in the adaptive cycling/handcycle forum, but it looks like it might fit in here and reach different viewers here. A little background on me to help explain my question. I'm paralyzed from the waist down for 31 years now. Using a wheelchair for that long has started taking its toll on my body, so I'm taking steps (no pun intended) to get in better shape and hopefully extend my time on this awesome planet. I've started lifting weights again after a 20 year layoff from it. I decided I needed to do something for cardio, too, and started looking into handcycles. After a lot of research, I found a used one and bought it. I've come to love it in the short time I've had it. I should have done this years ago! It's admittedly oriented toward cruising, not high performance. It's an Action brand, Top End model. As near as I can tell, the Top End brand started out as a model made by Action. For reference, this one is nearly identical to the current Top End Excelerator.

My only issue is that it spins out going up hills, and I just can't go up very steep hills because of this. I'd rather be limited on hills by my arms than by the front tire and to be able to climb steeper hills for more of a workout, but this limitation seems to be the nature of the design. It's driven by a single front wheel, and most of my 225 pound weight is on the pair of rear wheels. I've moved the seat forward as much as possible to help with this, but as I'm 6'4", I still sit pretty far back. It has a brand-new set of Kenda Kwest tires put on it by the previous owner. Tires are 26"x1.5"/40-559. 26"x2.0"s would fit with plenty of clearance. I'm considering going to one that size on the front for the slight width (and hopefully traction) increase. The Kenda Kwests are fairly slick, which should be better on the dry road, but don't seem very grippy. It also has a very rounded profile, so only a small, rounded patch actually contacts the road. I've aired it down to 40 PSI which seems to help a little. I don't anticipate any speeds above about 20 mph (downhill!), and average speeds closer to 7-8 mph, so high-speed turning or braking traction isn't a huge concern.

So my questions are around what to do to increase my uphill pulling traction on this single driven front wheel. Am I thinking correctly to go to a wider front tire and to run a lower pressure? Do you have any specific tire brand/model recommendations to maximize on-road driven traction? Are there any tire brands/models that have a flatter profile that would increase the contact patch? And, of course, I'm open to any other suggestions you more-experienced folks have for improving my uphill traction. I'm not looking to turn this cruiser into a high-performance handcycle, would just like to be able to tackle slightly steeper hills than I can currently. Thank you in advance for any recommendations you can provide.
FortMaceo is offline  
Old 06-22-22, 01:02 PM
  #2  
79pmooney
Senior Member
 
79pmooney's Avatar
 
Join Date: Oct 2014
Location: Portland, OR
Posts: 12,831

Bikes: (2) ti TiCycles, 2007 w/ triple and 2011 fixed, 1979 Peter Mooney, ~1983 Trek 420 now fixed and ~1973 Raleigh Carlton Competition gravel grinder

Mentioned: 128 Post(s)
Tagged: 0 Thread(s)
Quoted: 4746 Post(s)
Liked 3,862 Times in 2,511 Posts
Tire tread compounds vary a lot. I'd guess Kenda to be poor. (I've only used their tubes and I was not impressed.) Another aspect is sidewall flexibility; the more flex the better. Tread pattern too but I'd rate both compound and sidewall as being more important. (Tread patterns are great when the surface matches the tread but mis-matches can be poor.)

I don't know the options in 26". Panaracer certainly makes some and might make some using the tires of their better 700c/27" types. Vittoria makes some very good gripping tires but their focus is heavily on 700c. (If you could get a Corsa Control G+/G2.0 or Open Pave, jump on it. Race level good gripping tire. (If - and I know this might be a big "if" for you, you can manage a flat tire and get home.) The Panaracers are good all-around tires. Not immune to flats but they are not common. Popular tires from them are Pasela and Gravel King (and a third I'm not coming up with now). Continental might have a good tire in 26" but they may be more focused or tread wear, flat protection and rolling resistance, all of which subtract from pure traction.
79pmooney is offline  
Old 06-22-22, 01:02 PM
  #3  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,824

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1774 Post(s)
Liked 1,231 Times in 852 Posts
Is there room to install a front rack/basket that you could add weight to?
Bill Kapaun is offline  
Likes For Bill Kapaun:
Old 06-22-22, 02:14 PM
  #4  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Bill Kapaun
Is there room to install a front rack/basket that you could add weight to?
Bill, thank you for the idea. There's not really room for a basket or a rack. There is room for something like strap-on ankle weights. I might try that.
FortMaceo is offline  
Old 06-22-22, 02:19 PM
  #5  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by 79pmooney
Tire tread compounds vary a lot. I'd guess Kenda to be poor. (I've only used their tubes and I was not impressed.) Another aspect is sidewall flexibility; the more flex the better. Tread pattern too but I'd rate both compound and sidewall as being more important. (Tread patterns are great when the surface matches the tread but mis-matches can be poor.)

I don't know the options in 26". Panaracer certainly makes some and might make some using the tires of their better 700c/27" types. Vittoria makes some very good gripping tires but their focus is heavily on 700c. (If you could get a Corsa Control G+/G2.0 or Open Pave, jump on it. Race level good gripping tire. (If - and I know this might be a big "if" for you, you can manage a flat tire and get home.) The Panaracers are good all-around tires. Not immune to flats but they are not common. Popular tires from them are Pasela and Gravel King (and a third I'm not coming up with now). Continental might have a good tire in 26" but they may be more focused or tread wear, flat protection and rolling resistance, all of which subtract from pure traction.
Thank you for the suggestions and the information about tread compounds and sidewall flexibility. It is important for me to avoid flats if possible. Imagine changing out a tube on your bike with your full weight still sitting on the seat, which is what I'd have to do. I suspect I could figure it out, but would prefer not to! I'll look into the brands you mention. Thank you again for your help.
FortMaceo is offline  
Old 06-22-22, 02:23 PM
  #6  
ClydeClydeson
Senior Member
 
Join Date: Mar 2019
Posts: 1,606
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 581 Post(s)
Liked 921 Times in 518 Posts
Bill Kapaun 's idea is what I first thought - add something with some weight a bit further forward. A basket, a pair of water bottles, I don''t know what else. The further forward you mount the weight the more effect it will have, but likely too far forward will make whatever it is inaccessible from the driver's seat.

Another option is to lower the tire pressure in the front wheel. Since it has so little weight on it you can run it pretty low without fear of pinch flats. A tire at lower pressure will better follow the bumps in irregularities in the road and increase traction.
And while on the subject of tires, putting wider tires on the rear and a skinnier tire on the front (or simply more pressure in the R and less pressure in the F) will tilt the whole rig forward a bit, which will put marginally more weight on the front. Tires for 26" wheels are commonly available in widths from 1" up to 3+". 1.25 on the front and 2.5 on the rear will make a noticeable difference. You'll still want to run the front tire at pretty low pressure for maximum traction.

Being limited by the steepness of the road or trail is a common situation in mountain biking, and this leads to my final suggestion - practice applying the power in the smoothest possible circles to avoid any surges that will break the tire loose. I don't know you or how smooth you are so this may or may not be helpful advice.

Best of luck!
ClydeClydeson is offline  
Old 06-22-22, 02:57 PM
  #7  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by ClydeClydeson
Bill Kapaun 's idea is what I first thought - add something with some weight a bit further forward. A basket, a pair of water bottles, I don''t know what else. The further forward you mount the weight the more effect it will have, but likely too far forward will make whatever it is inaccessible from the driver's seat.

Another option is to lower the tire pressure in the front wheel. Since it has so little weight on it you can run it pretty low without fear of pinch flats. A tire at lower pressure will better follow the bumps in irregularities in the road and increase traction.
And while on the subject of tires, putting wider tires on the rear and a skinnier tire on the front (or simply more pressure in the R and less pressure in the F) will tilt the whole rig forward a bit, which will put marginally more weight on the front. Tires for 26" wheels are commonly available in widths from 1" up to 3+". 1.25 on the front and 2.5 on the rear will make a noticeable difference. You'll still want to run the front tire at pretty low pressure for maximum traction.

Being limited by the steepness of the road or trail is a common situation in mountain biking, and this leads to my final suggestion - practice applying the power in the smoothest possible circles to avoid any surges that will break the tire loose. I don't know you or how smooth you are so this may or may not be helpful advice.

Best of luck!
Clyde, thank you for all of the suggestions. Will try some weight out front and lower front tire pressure. Your idea for narrower front/wider rear tires is interesting. Do you think the traction lost from having a narrower tire would be overcome by the weight differential resulting from this technique?

I'll keep practicing applying power more smoothly. As I'm new to cycling, I'm certain that I have a lot of room for improvement there. Great suggestions, thank you again.
FortMaceo is offline  
Old 06-23-22, 05:09 AM
  #8  
AeroGut
Senior Member
 
Join Date: Jun 2019
Posts: 679
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 254 Post(s)
Likes: 0
Liked 182 Times in 141 Posts
Looking at pictures of the bike, it appears that you could use hose clamps or something like that to attach weights to each side of the fork (like what some bikepackers do with extra gear or water bottles), as long as you're careful not to interfere with the chain. Maybe try 10 lbs on each side. Of course, that means more weight to push up the hills, but it'll help push the front wheel down. It's hard to tell if the footrest positions are adjustable, but if they are, moving those as far forward as possible without interfering with the front wheel will also help.
The fundamental problem seems to be that the frame is only made in one size, so a taller rider like yourself in variably ends up with weight farther back relative to the rear axle.
AeroGut is offline  
Old 06-23-22, 07:24 AM
  #9  
ClydeClydeson
Senior Member
 
Join Date: Mar 2019
Posts: 1,606
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 581 Post(s)
Liked 921 Times in 518 Posts
Originally Posted by FortMaceo
Do you think the traction lost from having a narrower tire would be overcome by the weight differential resulting from this technique?
Traction is a function of (on a smooth surface) the weight pushing down and the coefficient of friction between the two materials. On a rough surface, the ability of the tire to conform to road irregularities plays a big part, and this is directly related to the size of the contact patch, which is a function of the weight on the wheel and the pressure in the tire. So if the weight pushing down on the tire stays roughly the same and you have the same pressure in the tire, the traction should be the same. All this is to say you shouldn't have a noticeable drop in traction if you swap to a narrower tire and keep the pressure in the tire the same. Wider tires give better traction mostly because they can be run at lower pressures without fear of getting pinch flats, but if your front wheel is almost 'floating' because of the balance of the bike, then you can run it quite low. As long as the rim isn't bottoming out against the tire and ground when you hit bumps then you are good.

You can try simply lowering the pressure in the tire you have before changing anything else. This would be my first step.
ClydeClydeson is offline  
Old 06-23-22, 08:51 AM
  #10  
_ForceD_
Sr Member on Sr bikes
 
_ForceD_'s Avatar
 
Join Date: Jul 2015
Location: Rhode Island (sometimes in SE Florida)
Posts: 2,307

Bikes: Several...from old junk to new all-carbon.

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1012 Post(s)
Liked 762 Times in 409 Posts
Just for reference, I presume the picture below is the handcycle you’re talking about? And also…pardon my crude artwork.

It’d take a bit of reconfiguring, but I wonder if you could somehow reconfigure the stirrups/foot rests, or have some created, that attach so that the rests are out front, over the front axle, instead of underneath you. That way, the weight of your legs would be out over the axle instead of underneath you. It looks like the stirrups that come with the cycle can be removed, and reattached in that way…maybe??? Or you could have some made that attach that way. — Dan

_ForceD_ is offline  
Likes For _ForceD_:
Old 06-23-22, 08:54 AM
  #11  
redcon1
Senior Member
 
redcon1's Avatar
 
Join Date: Aug 2008
Location: South Central PA
Posts: 549

Bikes: Focus Arriba, Specialized Roubaix Expert, Bianchi Impulso Allroad

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 82 Times in 53 Posts
I see the Top End Accelerator model and others have 24" wheels... is yours actually 26?" I'm hoping so, because 26" high-quality tires will more available than 24", for sure.
The idea to put a wider tire running lower pressure up front for better traction is my recommendation. I converted a 26" hardtail MTB to run on the road and ran some excellent Continental Grand Prix tires

Shifting some weight forward will also help, but there comes a point of diminishing returns -- due to lugging extra weight up the hills. Ideally something you already need to carry - I.e. water, saddle/frame bag, etc. would be a great choice
redcon1 is offline  
Likes For redcon1:
Old 06-23-22, 02:19 PM
  #12  
Crankycrank
Senior Member
 
Join Date: Jan 2009
Location: San Diego, CA
Posts: 3,651
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 835 Post(s)
Liked 1,057 Times in 741 Posts
I'm wondering if you could install a spacer, maybe 1" or 2" in the horizontal section of the maintube where it has a 4 bolt connection. Would move the front end forward and you could then move the seat forward while still having enough room for your height and would add slightly more of the weight distribution to the front.
Crankycrank is offline  
Old 06-23-22, 06:28 PM
  #13  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by AeroGut
Looking at pictures of the bike, it appears that you could use hose clamps or something like that to attach weights to each side of the fork (like what some bikepackers do with extra gear or water bottles), as long as you're careful not to interfere with the chain. Maybe try 10 lbs on each side. Of course, that means more weight to push up the hills, but it'll help push the front wheel down. It's hard to tell if the footrest positions are adjustable, but if they are, moving those as far forward as possible without interfering with the front wheel will also help.
The fundamental problem seems to be that the frame is only made in one size, so a taller rider like yourself in variably ends up with weight farther back relative to the rear axle.
You're correct that I'm somewhat limited by my height and huge feet. I do think that I can adjust the footrests forward an inch or so. Will give that a try, as it will move some weight forward. And I agree that I can get some relatively-small weights of some kind of the sides of the fork. Thank you for the suggestions!
FortMaceo is offline  
Old 06-23-22, 06:30 PM
  #14  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by ClydeClydeson
Traction is a function of (on a smooth surface) the weight pushing down and the coefficient of friction between the two materials. On a rough surface, the ability of the tire to conform to road irregularities plays a big part, and this is directly related to the size of the contact patch, which is a function of the weight on the wheel and the pressure in the tire. So if the weight pushing down on the tire stays roughly the same and you have the same pressure in the tire, the traction should be the same. All this is to say you shouldn't have a noticeable drop in traction if you swap to a narrower tire and keep the pressure in the tire the same. Wider tires give better traction mostly because they can be run at lower pressures without fear of getting pinch flats, but if your front wheel is almost 'floating' because of the balance of the bike, then you can run it quite low. As long as the rim isn't bottoming out against the tire and ground when you hit bumps then you are good.

You can try simply lowering the pressure in the tire you have before changing anything else. This would be my first step.
Thank you for the additional explanation. That makes sense. I'll keep going down on front tire pressure and see how it goes.
FortMaceo is offline  
Old 06-23-22, 08:05 PM
  #15  
rm -rf
don't try this at home.
 
rm -rf's Avatar
 
Join Date: Jan 2006
Location: N. KY
Posts: 5,918
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 964 Post(s)
Liked 496 Times in 343 Posts
I don't think added weights will help enough to notice. Sliding your weight forward sounds helpful.
I was going to suggest a pricey slick tire with grippy rubber, as wide as will fit.
These Rene Herse tires are the extreme example, very grippy, 2.3 inch wide, and $$$. Rat Trap Pass 26x2.3

A few complications, though:
It looks like only the front wheel has brakes? is it a drum brake or a rim brake?
Rim brakes will also limit the tire width. How wide can the brake pads separate when when they are unlatched from their riding position for wheel removal?

Low pressures will help. For a reasonable pressure, I'd look for a slight widening of the tire sides where they contact the road. Since the weight on the tire seems low, this might be quite low pressure! The "rule of thumb" on a road bike is a 15% height drop where the tire flattens against the road with the rider's weight on the tires. That allows flexing over rough road surfaces, but with minimal pinch flat problems.

You are depending on this one wheel for steering and braking, so flats on a downhill would be bad. That kind of limits just how lightweight a tire you would want.

And too low a pressure makes pinch flats more likely. But pinch flats are related to how tall and how sharp edged the pothole / rock / debris is, and how fast the rider is going. The tire just bumps over a squared rock chunk at low speeds, but compresses to the rim at high speeds, causing the pinch flat.

Tire width vs pressure.
Pressures are proportional to the square of the width (the interior circular cross section is that familiar formula, pi x radius squared)
A 2 inch tire has about 75% more air volume than a 1.5 tire! Surprising. So maybe 25 psi on a 2 inch tire instead of the 40 psi on the 1.5 tire.

Last edited by rm -rf; 06-23-22 at 08:13 PM.
rm -rf is offline  
Old 06-24-22, 05:19 AM
  #16  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by _ForceD_
Just for reference, I presume the picture below is the handcycle you’re talking about? And also…pardon my crude artwork.

It’d take a bit of reconfiguring, but I wonder if you could somehow reconfigure the stirrups/foot rests, or have some created, that attach so that the rests are out front, over the front axle, instead of underneath you. That way, the weight of your legs would be out over the axle instead of underneath you. It looks like the stirrups that come with the cycle can be removed, and reattached in that way…maybe??? Or you could have some made that attach that way. — Dan
Dan, thank you for the artwork and suggestion. The "sportier" handcycles come with footrests like you're suggesting - out by the front wheel instead of low, in front of the seat. Probably because the seat is much lower on them, but also because of weight distribution. I can fab footrests like that and might give it a try if some of the easier ideas don't work. Thank you again.
FortMaceo is offline  
Likes For FortMaceo:
Old 06-24-22, 05:23 AM
  #17  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by redcon1
I see the Top End Accelerator model and others have 24" wheels... is yours actually 26?" I'm hoping so, because 26" high-quality tires will more available than 24", for sure.
The idea to put a wider tire running lower pressure up front for better traction is my recommendation. I converted a 26" hardtail MTB to run on the road and ran some excellent Continental Grand Prix tires

Shifting some weight forward will also help, but there comes a point of diminishing returns -- due to lugging extra weight up the hills. Ideally something you already need to carry - I.e. water, saddle/frame bag, etc. would be a great choice
Good catch. I hadn't noticed that Top End's similar bike uses 24" tires. Mine (on this Action brand) are definitely 26". Did those Continental tires have pretty good grip?

I'll get some weight out on the fork, too. Still looking into how to do it without interfering with the chain or with my knees when I transfer on to/off of it but I'll figure it out. Thank you for your suggestions!
FortMaceo is offline  
Old 06-24-22, 05:26 AM
  #18  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Crankycrank
I'm wondering if you could install a spacer, maybe 1" or 2" in the horizontal section of the maintube where it has a 4 bolt connection. Would move the front end forward and you could then move the seat forward while still having enough room for your height and would add slightly more of the weight distribution to the front.
Good thought, but that's another slight difference in mine and the later Top End model. Mine doesn't have that connection mid-frame. If it did, I'd add an extender in there. Could still be done with some cutting and welding, but obviously harder. Thank you for the suggestion!
FortMaceo is offline  
Old 06-25-22, 06:47 AM
  #19  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by rm -rf
I don't think added weights will help enough to notice. Sliding your weight forward sounds helpful.
I was going to suggest a pricey slick tire with grippy rubber, as wide as will fit.
These Rene Herse tires are the extreme example, very grippy, 2.3 inch wide, and $$$. Rat Trap Pass 26x2.3

A few complications, though:
It looks like only the front wheel has brakes? is it a drum brake or a rim brake?
Rim brakes will also limit the tire width. How wide can the brake pads separate when when they are unlatched from their riding position for wheel removal?

Low pressures will help. For a reasonable pressure, I'd look for a slight widening of the tire sides where they contact the road. Since the weight on the tire seems low, this might be quite low pressure! The "rule of thumb" on a road bike is a 15% height drop where the tire flattens against the road with the rider's weight on the tires. That allows flexing over rough road surfaces, but with minimal pinch flat problems.

You are depending on this one wheel for steering and braking, so flats on a downhill would be bad. That kind of limits just how lightweight a tire you would want.

And too low a pressure makes pinch flats more likely. But pinch flats are related to how tall and how sharp edged the pothole / rock / debris is, and how fast the rider is going. The tire just bumps over a squared rock chunk at low speeds, but compresses to the rim at high speeds, causing the pinch flat.

Tire width vs pressure.
Pressures are proportional to the square of the width (the interior circular cross section is that familiar formula, pi x radius squared)
A 2 inch tire has about 75% more air volume than a 1.5 tire! Surprising. So maybe 25 psi on a 2 inch tire instead of the 40 psi on the 1.5 tire.
Thank you for the information. I'll look into that tire brand, and definitely appreciate the explanation about tire pressures and pinch flats. I've got a lot to learn and appreciate you helping me get started on it! On your question, yes, only the front wheel has brakes. The rim brake you see is intended as a parking brake to keep it steady while I'm getting on to/off of it. For riding brakes, you pedal backwards slightly so you don't have to give up a steering hand to grab the brake lever. Not sure what it's called, but it's like the one on my BMX bike when I was a kid. I measured the rim brake as you suggest and think I can get a 2.5" tire through that gap, especially if it's aired down somewhat. I'm not sure if the ~1" rim will work with a 2.5" tire, though, so probably looking at a 2" max.
FortMaceo is offline  
Old 06-25-22, 11:57 AM
  #20  
jccaclimber
Senior Member
 
Join Date: May 2005
Location: SFBay
Posts: 2,334

Bikes: n, I would like n+1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Likes: 0
Liked 133 Times in 108 Posts
This is an interesting issue that really has its root in poor frame design/fitting. It seems the manufacturer tried to solve a poor turning radius problem by pushing the real wheels as far forward as possible.

Assuming we’re talking cleanish dry pavement only, and not a moist grassy hill, the differences between one size or brand of tire and another are going to be pretty minor at best once you’re running slicks at the correct pressure. Given your disadvantage with tire changes I would run extra thick tubes just to decrease the odds of getting a puncture from a piece of glass.

Really what you want to do is shove the rear wheels backward, but I don’t see a good way to do that other than a frame modification, which a frame builder may or may not want to do. Lengthening it changes the forces on the rest of the tube, and I don’t know how much overhead is in the original design.

Your only other option is more weight forwards. Adding weight to the frame, or something rigged to it, will have a different impact to handling than something rigged to the fork, so you might try both.

Really it sounds like a different bike is needed, but I’m well aware of how uncommon handcycles are to begin with.

As previously mentioned, concentrating on smooth power delivery will definitely help.
jccaclimber is offline  
Old 06-26-22, 07:23 AM
  #21  
FortMaceo
Junior Member
Thread Starter
 
Join Date: Jun 2022
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by jccaclimber
This is an interesting issue that really has its root in poor frame design/fitting. It seems the manufacturer tried to solve a poor turning radius problem by pushing the real wheels as far forward as possible.

Assuming we’re talking cleanish dry pavement only, and not a moist grassy hill, the differences between one size or brand of tire and another are going to be pretty minor at best once you’re running slicks at the correct pressure. Given your disadvantage with tire changes I would run extra thick tubes just to decrease the odds of getting a puncture from a piece of glass.

Really what you want to do is shove the rear wheels backward, but I don’t see a good way to do that other than a frame modification, which a frame builder may or may not want to do. Lengthening it changes the forces on the rest of the tube, and I don’t know how much overhead is in the original design.

Your only other option is more weight forwards. Adding weight to the frame, or something rigged to it, will have a different impact to handling than something rigged to the fork, so you might try both.

Really it sounds like a different bike is needed, but I’m well aware of how uncommon handcycles are to begin with.

As previously mentioned, concentrating on smooth power delivery will definitely help.
Thank you for the thoughts. I agree that I'm pretty limited by the frame design. Some of the lower, sportier ones are built exactly like you're saying: longer frame, rear wheels further back (hence more weight on the front wheel). Once I get more used to this one and build myself up to exceed what it can do, I might end up with a better one.
FortMaceo is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.