La Bicycletta

[Xstr8edgtnrdrmrX]

This looks like what I need here. It's modern so parts will be easy to find. It's light. It looks way cool. And it's 26 in rims. For what I use a bike for - daily riding for exercise and errands - I think this is perfect:

Carbon fiber Mountain bike 27 speed mountain 26" rims, 17 inch -...

Eurobike 980CB - Carbon Fiber Price: $1050 Colors: Black/Red/White Size 17" 170-180 cm Carbon Fiber Frame 3x9 Speed Alloy Suspension Fork with Lock Control Carbon Handle Bar and Stem Shimano MT200...

chicago.craigslist.org

It says full suspension, but I can only locate suspension on the forks, making this a hardtail MTB.

is it actually a Scott 980cb? I can't get CL at work, but looked up the model number at Eurobike...it is a hardtail

 

[rhumbagirl]

is it actually a Scott 980cb? I can't get CL at work, but looked up the model number at Eurobike...it is a hardtail

Don't know. Who is Scott? I'm probably going to throttle back my search while the Wheels Manufacturing 4130 axle gets shipped to me. All the indicators are pointing to a 26 in wheel with freehub and 8-spd derailler set and new shifters. But I do need a used bike while I screw with the current one.

 

[someguy01]

https://www.scott-sports.com/us/en/sports/bike

 

[rhumbagirl]

https://www.scott-sports.com/us/en/sports/bike

Well I peeked and wha la, I found a bike shop near me in Pensacola, FL. I may not purchase a Scott, but I bet the shops that sell them are pretty good ones!

 

[rhumbagirl]

So I got tired of explaining bicycle measurements to sellers on ebay and made this colorful chart. Stack and reach are probably the main measurements for standup riders, although the effective top tube length would help determine frame size. But how do you explain to the average joe what a plumb line is and how to use it? I think it would very challenging for the average joe to hold the plumb steady while measuring the horizontal distance to the top-center of head tube simultaneously.

 

[cbphoto]

So I got tired of explaining bicycle measurements to sellers on ebay and made this colorful chart. Stack and reach are probably the main measurements for standup riders, although the effective top tube length would help determine frame size. But how do you explain to the average joe what a plumb line is and how to use it? I think it would very challenging for the average joe to hold the plumb steady while measuring the horizontal distance to the top-center of head tube simultaneously.

View attachment 112611

Looks like what someone actually needs is a custom frame set. 🤔

 

[rhumbagirl]

Looks like what someone actually needs is a custom frame set. 🤔

What do you think about Specialized MTBs? Here's a 2002 Rockhopper on ebay for $499 used. I think that's what they cost new:

Specialized Rockhopper Comp A1 17” Frame 26” Wheel Mountain Bike Red Suspension | eBay

Find many great new & used options and get the best deals for Specialized Rockhopper Comp A1 17” Frame 26” Wheel Mountain Bike Red Suspension at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[Xstr8edgtnrdrmrX]

So I got tired of explaining bicycle measurements to sellers on ebay and made this colorful chart. Stack and reach are probably the main measurements for standup riders, although the effective top tube length would help determine frame size. But how do you explain to the average joe what a plumb line is and how to use it? I think it would very challenging for the average joe to hold the plumb steady while measuring the horizontal distance to the top-center of head tube simultaneously.

View attachment 112611

I think the average joe selling a bike on CL,eBay or whatever is not going to put the effort into doing this much math honestly...

But you could explain a plumb line as a string with a weight on the end that determines "true vertical", and that the angles in your diagram are based on this true vertical establishment...

hell, I have been biking for 40+ years, and still really only know the difference in angles by feel...like, i know when a bike feels right. Only recently have I really been able to translate the numbers to a feel

 

[rhumbagirl]

hell, I have been biking for 40+ years, and still really only know the difference in angles by feel...like, i know when a bike feels right. Only recently have I really been able to translate the numbers to a feel

Maybe. Maybe I can ... well I *should* be able to measure the angles of the head tube, seat tube, top tube and bottom tube - and calculate the reach and effective top tube length.

Sally can't tell Oscar has a harry old ass:
Sine, Cosine, Tangent = Opposite / Hypotenuse, Adjacent / Hypotenuse, Opposite / Adjacent

 

[Xstr8edgtnrdrmrX]

Maybe. Maybe I can ... well I *should* be able to measure the angles of the head tube, seat tube, top tube and bottom tube - and calculate the reach and effective top tube length.

Sally can't tell Oscar has a harry old ass:
Sine, Cosine, Tangent = Opposite / Hypotenuse, Adjacent / Hypotenuse, Opposite / Adjacent

I learned more about how the angles affect my riding in BMX than anything else.

A higher HT angle makes the bike more twitchy
A longer chainstay makes the bike more stable
TT length determines "fit" of bike and cockpit
BB height and ST angle affect standover(?)
A lower ST angle and HT angle makes the bike more slack <---from MTB

 

[rhumbagirl]

I learned more about how the angles affect my riding in BMX than anything else.

A higher HT angle makes the bike more twitchy
A longer chainstay makes the bike more stable
TT length determines "fit" of bike and cockpit
BB height and ST angle affect standover(?)
A lower ST angle and HT angle makes the bike more slack <---from MTB

I think the BB drop is small on a 26 in MTB because the small 26 in wheels puts the frame and the BB (and crank) closer to the ground. Don't want riders' feet hitting the ground while pedaling.

A longer chainstay makes the wheel base longer which removes stability at slower speeds.

Agree that BB height would affect standover, but not sure how ST *angle* does (ST height, definitely).

Agree on slack. That's something I'm not concerned about at 9-12mph average speed. I'd rather have stability up hills and turning tight corners (I ride on sidewalks, navigating around people, dodging glass, nails, pot holes).

 

[Xstr8edgtnrdrmrX]

I think the BB drop is small on a 26 in MTB because the small 26 in wheels puts the frame and the BB (and crank) closer to the ground. Don't want riders' feet hitting the ground while pedaling.

A longer chainstay makes the wheel base longer which removes stability at slower speeds.

Agree that BB height would affect standover, but not sure how ST *angle* does (ST height, definitely).

Agree on slack. That's something I'm not concerned about at 9-12mph average speed. I'd rather have stability up hills and turning tight corners (I ride on sidewalks, navigating around people, dodging glass, nails, pot holes).

yeah 26ers are definitely closer to the ground by nature. My commuter is an old Trek 830 26er...it is perfect for that kind of riding. I can't believe it was actually sold as a MTB originally!! I would have destroyed that bike on the dirt

my current 29+ MTB still "bottoms out" sometimes if I am not carefull about how I approach things on the trail

and honestly, I would rather ride dirt than city riding because I can't stand drivers, but I do commute in the summer

 

[cbphoto]

What do you think about Specialized MTBs? Here's a 2002 Rockhopper on ebay for $499 used. I think that's what they cost new:

Specialized Rockhopper Comp A1 17” Frame 26” Wheel Mountain Bike Red Suspension | eBay

Find many great new & used options and get the best deals for Specialized Rockhopper Comp A1 17” Frame 26” Wheel Mountain Bike Red Suspension at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I think you’d be settling, but I’ve not ridden that design for any distance.

 

[rhumbagirl]

I think you’d be settling, but I’ve not ridden that design for any distance.

Maybe. I did happen upon the Specialized "Stumpjumper", which is supposedly a souped-up Rockhopper. The problem is the Stumpjumpers I've located so far are too big in the frame size. The Rockhopper 17" above was even too big - 15.2/14.75 reach, 22.5/21.25 effective top tube length (their's/mine). Apparently the frame size for some MTBs are not aligning to the same for my Diamondback 18". I don't think they treat women's and men's bikes differently like they do shoes, but I suppose it could be the reason.

Anyway, I like the look of the Stumpjumper, and just want to find one with a smaller frame. Reach and Effective Top Tube Length are still the numbers that don't lie. Standover is important, but I don't see that number flying around a lot in the specs.

Correction: Reach for the Rockhopper is 15.2 in (not 15.5). This represents only 0.5 inch difference, but the Effective Top Tube difference is 1.25 in. That means the seat is 0.75 in further back than mine.

 

[cbphoto]

Maybe. I did happen upon the Specialized "Stumpjumper", which is supposedly a souped-up Rockhopper. The problem is the Stumpjumpers I've located so far are too big in the frame size. The Rockhopper 17" above was even too big - 15.5/14.75 reach, 22.5/21.25 effective top tube length (their's/mine). Apparently the frame size for some MTBs are not aligning to the same for my Diamondback 18". I don't think they treat women's and men's bikes differently like they do shoes, but I suppose it could be the reason.

Anyway, I like the look of the Stumpjumper, and just want to find one with a smaller frame. Reach and Effective Top Tube Length are still the numbers that don't lie. Standover is important, but I don't see that number flying around a lot in the specs.

As I’ve been following this thread, I’ve poked around at various bicycle sites. I’m still shocked that two different tires sizes is considered an option, and there’s 29” tires and front forks without the fork! I’ve been out of the loop a long time.

The Stumpjumper was the first model Specialized introduced in the 1980s. It morphed a few times and by the early 1990s the Rockhopper was introduced at a lower price point. I have an original Stumpjumper and it’s old-school frame design: the seat tube is long. I don’t know what the geometry is on anything later than what I own. The newer designs would probably suit you better if you like to jump & fly & slide. If you like to cruise and speed around with street tires on asphalt, an old Stumpjumper would be perfect. I believe they also came in very small frame sizes.

Still, I’m honestly very surprised you can’t find a new, decent MTB with 26” wheels.

 

[rhumbagirl]

... and front forks without the fork!

That's both cool and silly at the same time LOL. I wonder what kind of metal they're using for that front hub. I'm not a materials engineer but isn't titanium the hardest metal??

Anyway, I found a triangle calculator on the web, and it works for all triangles, not just right triangles (triangles where one of the vertices is 90 deg):

Calculation of the obtuse scalene triangle from general data - sides a, b, and angle γ: triangle γ=93 b=14 a=21

21 14 25.841 - Obtuse scalene triangle, area=146.8. Computed angles, perimeter, medians, heights, centroid, inradius and other properties of this triangle.

www.triangle-calculator.com

(If you don't know where the beta symbol is on your keyboard - I don't - then just find it on the page and copy n paste)

 

[cbphoto]

That's both cool and silly at the same time LOL. I wonder what kind of metal they're using for that front hub. I'm not a materials engineer but isn't titanium the hardest metal??

Yes, those bikes are all custom-built using titanium.

Anyway, I found a triangle calculator on the web, and it works for all triangles, not just right triangles (triangles where one of the vertices is 90 deg):

Calculation of the obtuse scalene triangle from general data - sides a, b, and angle γ: triangle γ=93 b=14 a=21

21 14 25.841 - Obtuse scalene triangle, area=146.8. Computed angles, perimeter, medians, heights, centroid, inradius and other properties of this triangle.

www.triangle-calculator.com

(If you don't know where the beta symbol is on your keyboard - I don't - then just find it on the page and copy n paste)

On a Mac, using option-s I get: ß

 

[rhumbagirl]

As I’ve been following this thread, I’ve poked around at various bicycle sites.

That's quite a list of custom frame shops in the USA. The first one I clicked on - Spectrum Bikes - closed last year. The second one - K. Bedford Customs - was pretty cool stuff (eg titanium frames!).

I suppose the next question is can they make a custom Stumpjumper frame, so all I would have to do is buy any old Stumpjumper and transfer the parts over. Although at that point, you'd be dumb not to go get the newest parts out there. $$$

 

[Xstr8edgtnrdrmrX]

That's quite a list of custom frame shops in the USA. The first one I clicked on - Spectrum Bikes - closed last year. The second one - K. Bedford Customs - was pretty cool stuff (eg titanium frames!).

I suppose the next question is can they make a custom Stumpjumper frame, so all I would have to do is buy any old Stumpjumper and transfer the parts over. Although at that point, you'd be dumb not to go get the newest parts out there. $$$

you should look into waltworks frames as well : https://waltworks.com/framesandbikes/

he is a very very cool guy who has been making frames forever

 

[MrInsanePolack]

I just read this article:

Mechanics Ask Walmart, Major Bike Manufacturers to Stop Making and Selling ‘Built-to-Fail’ Bikes

“The problem with budget bikes is everything. They’re literally built to fail.”

www.vice.com

What say you, bike people? Should Walmart stop selling bikes to those who just want a bike and arent serious riders? I get the gripe, but average kids mom and dad arent going to buy a $500 first bike that he might not even ride. Would removing cheap bikes from department stores deter folks from wanting to ride a bike?