Setting up Rize Pro RX (or any 26" fatty) as a hybrid on/off road bike......

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Loving most of the things regarding the bike. Everything working well, but I would say that the 4" tires were a mistake - FOR ME/MY purposes! Rolling resistance seems high (even with 20 psi) , and the bike FEELS big.

I'm not real crazy about the stock front fork (pogo stick), so I was in the process of shopping to replace that with a much nicer air fork. That's when the thought occurred to me, if I'm going to be making that move, why not get a fork set up for 27.5" wheels - a 100mm width fork vs. the stock 135mm set for 4" tires? Convert the front of the bike to 27.5"? Overall height of the 27.5" tires not likely any bigger than the current 26"x3" on it now, so none of the angles that might affect handling would change much.

Thoughts? Anyone done this, or something similar? -Al
 

Bubba zanetti

Active Member
Region
Canada
City
Trail, BC
I can’t remember the review but a recent bike had a 27.5 front and 26 rear Stock.
something to do with mechanical advantage of a smaller drive wheel. My RX has 2.4 tires and I quite like them. I’m seriously looking at the Schwable Marathons. Quiet center strip but off-road capable.
Im with you on the forks too. Trying to educate myself about which ones will swap in. So will follow along with your learning.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
I have a set of 26x2" Marathons on another bike - the one with the big MAC 12t motor. They are not only silent under all conditions, the rolling resistance is very low. Highly recommend them!

That said, they are not the best riding tire. They transmit every small rock, pavement crack, etc. right up into the bike frame - even at just 55psi.

Soooo, I have one of these on the way. Going to try it in back first, and if that works well, we'll get a second. From what I understand these are fairly new, and are approved for use on e-bikes. -Al
https://www.amazon.com/gp/product/B07GTKPJLH/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
These are what I have on the small bike right now -

I don't know that much about why the current tires are running so rough. I just assumed that the bigger the tire size, the less pressure would be required to support my weight, AND, the extra sidewall height allowed more room to flex?

Agree the flat protection could have something to do with it as well. -Al
 

Gionnirocket

Well-Known Member
Region
USA
City
Y. O.
These are what I have on the small bike right now -

I don't know that much about why the current tires are running so rough. I just assumed that the bigger the tire size, the less pressure would be required to support my weight, AND, the extra sidewall height allowed more room to flex?

Agree the flat protection could have something to do with it as well. -Al
Flat protection definitely stiffens a tire and affects ride quality some.

Schwalbe makes things confusing calling different tread patterns Marathon.
 

theemartymac

Well-Known Member
I can’t remember the review but a recent bike had a 27.5 front and 26 rear Stock.
something to do with mechanical advantage of a smaller drive wheel. My RX has 2.4 tires and I quite like them. I’m seriously looking at the Schwable Marathons. Quiet center strip but off-road capable.
Im with you on the forks too. Trying to educate myself about which ones will swap in. So will follow along with your learning.
That was not uncommon in downhill bikes on the pro race circuit, or the freeride scene. You may want the smaller rear wheel for improved gear ratio in climbs and overall stiffness in the shorter suspension frame, but the larger front wheel to smooth out the transitions over roots and logs. The lowered rear also helped flatten the profile of the bike on descents, which meant you didn't have to hang so far off the rear, upsetting the center of gravity and front wheel handling.

It's not as big a deal anymore as there are so many customized frame geometries now that you can spec anything you want, but there is no reason it couldn't be done with a disc brake bike (obviously rim brakes don't play well with non-standard configurations). The biggest consideration on a 'flat' terrain bike is that too much change will change the angles of the headset tube, and more rake means slower steering and suspension rebound (while taking big hits like curbs a bit better). 2 inches change may not even be noticeable on a casual bike, but would on a high speed race bike.

Now if you went smaller on the front without careful consideration, you could be in a world of pain. As a more upright headset makes the bike turn fast and twitchy, and the suspension is overstressed because it's always being torqued to the rear on impact. Obviously if you didn't compensate for the forward center of gravity with a shorter handlebar stem and seat offset you, would be far more likely to end up in front of your ride after an unforeseen pothole or impact.
 

Bubba zanetti

Active Member
Region
Canada
City
Trail, BC
That was not uncommon in downhill bikes on the pro race circuit, or the freeride scene. You may want the smaller rear wheel for improved gear ratio in climbs and overall stiffness in the shorter suspension frame, but the larger front wheel to smooth out the transitions over roots and logs. The lowered rear also helped flatten the profile of the bike on descents, which meant you didn't have to hang so far off the rear, upsetting the center of gravity and front wheel handling.

It's not as big a deal anymore as there are so many customized frame geometries now that you can spec anything you want, but there is no reason it couldn't be done with a disc brake bike (obviously rim brakes don't play well with non-standard configurations). The biggest consideration on a 'flat' terrain bike is that too much change will change the angles of the headset tube, and more rake means slower steering and suspension rebound (while taking big hits like curbs a bit better). 2 inches change may not even be noticeable on a casual bike, but would on a high speed race bike.

Now if you went smaller on the front without careful consideration, you could be in a world of pain. As a more upright headset makes the bike turn fast and twitchy, and the suspension is overstressed because it's always being torqued to the rear on impact. Obviously if you didn't compensate for the forward center of gravity with a shorter handlebar stem and seat offset you, would be far more likely to end up in front of your ride after an unforeseen pothole or impact.
Thanks. Makes sense.
Any thoughts on an air forks of improved quality for the Rize RX? Im not deluded to think it’s a MTB, Just looking to take the pogo like lack of compression and excessive rebound out with a better quality setup?
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
That was not uncommon in downhill bikes on the pro race circuit, or the freeride scene. You may want the smaller rear wheel for improved gear ratio in climbs and overall stiffness in the shorter suspension frame, but the larger front wheel to smooth out the transitions over roots and logs. The lowered rear also helped flatten the profile of the bike on descents, which meant you didn't have to hang so far off the rear, upsetting the center of gravity and front wheel handling.

It's not as big a deal anymore as there are so many customized frame geometries now that you can spec anything you want, but there is no reason it couldn't be done with a disc brake bike (obviously rim brakes don't play well with non-standard configurations). The biggest consideration on a 'flat' terrain bike is that too much change will change the angles of the headset tube, and more rake means slower steering and suspension rebound (while taking big hits like curbs a bit better). 2 inches change may not even be noticeable on a casual bike, but would on a high speed race bike.

Now if you went smaller on the front without careful consideration, you could be in a world of pain. As a more upright headset makes the bike turn fast and twitchy, and the suspension is overstressed because it's always being torqued to the rear on impact. Obviously if you didn't compensate for the forward center of gravity with a shorter handlebar stem and seat offset you, would be far more likely to end up in front of your ride after an unforeseen pothole or impact.
All good thoughts. Thing is it looks like when speaking in general, the outside diameter 26x3 vs. something like a 27.5x2.3 are not that different. As measured a few minutes ago-
26x3"=27.5"
27.5x1.9=27.2"
26x2" (Marathon)=26"
So there's that. I had seen mention of this previously, so no surprise.

The surprise happened when I follow the fork angle and measure from the ground to the bottom of the head race. Here there's a pretty significant difference when comparing 26 fatty w/135mm drop out vs. the 27.5" fork w/100mm drop out. I had to measure this 3 times, because it doesn't sound right when seeing the bikes sitting side by side. Made me wonder if I hadn't become a little befuddled?

The fatty measures 34", while the 27.5" measures 32.5". So the fatty, though you would think the head race LOOKS lower, is actually 1.5" higher!

So I measured from the drop outs to the bottom of the head race to confirms this.
27.5" fork measures 19.5"
26" fatty measures 21"

So, to summarize, when a 26" fatty rolls over a root, the big sidewall is going to deflect more, but the 27.5, because it's NOT deflecting more, should roll over it easier - and will likely do that with more of a jolt - hopefully to be minimized by a decent set of forks.

The head angle is going to change making this swap, to a very small degree I think, but it will change. The question might be will the change be noticeable to Joe average hybrid bike rider? There's also the question that wonders if all forks are created equally, Will the new air forks measure similarly to the pogo sticks I have now?

Noteworthy is I made no attempt at measuring accurately to the nth degree, and the measurements were pulled from bikes sitting in the garage. -Al
 

theemartymac

Well-Known Member
Thanks. Makes sense.
Any thoughts on an air forks of improved quality for the Rize RX? Im not deluded to think it’s a MTB, Just looking to take the pogo like lack of compression and excessive rebound out with a better quality setup?
It's on my list of to do's, perhaps for later this season if supplies and prices stabilize (and after the warranty period is expired). I will definitely be trying to source a mid-range air shock but honestly haven't done a lot of research on it yet for this bike with the market like it is. it's certain to be a measurable improvement, but also definitely just a "nice-to-have' upgrade for the riding I do in my old age.
 

theemartymac

Well-Known Member
So, to summarize, when a 26" fatty rolls over a root, the big sidewall is going to deflect more, but the 27.5, because it's NOT deflecting more, should roll over it easier - and will likely do that with more of a jolt - hopefully to be minimized by a decent set of forks.

The head angle is going to change making this swap, to a very small degree I think, but it will change. The question might be will the change be noticeable to Joe average hybrid bike rider? There's also the question that wonders if all forks are created equally, Will the new air forks measure similarly to the pogo sticks I have now?
Have you seen this thread?


And the video linked with it a few posts down may be informative for the actual riding feedback as well. Although he is riding much more serious terrain, the basic feedback is probably fair.