v1nce

It occured to me that two of the most critical dimensions for folding bikes are wheelbase and reach. The former being the most crucial since it can often not be altered in any significant way. Also wheelbase can have a huge impact on handling, speed and comfort, possibly even more than wheelsize. Perhaps we can make a list of these measurements for folders (in their stock form). For the wheelbase i suggest two measurements, Axle to Axle distance and possibly Rim edge to Rim edge (to discount tire variations).

I for example was surprised to learn that both sizes were slightly greater on the 16 inch Brompton than on my 20 inch Twenty.

For reach another three measurements perhaps. Minumum & Maximum extension. Distance of stem to saddle when they are in stock positio, perhaps a range etc.

This is a lot of sizes, but i for one would value axle to axle lots already. Some of the bikes i'd like to know these sizes for : Breezers, DT's, Dahons, Brommies, Twenties, Swifts (is already online right?) BF, etc etc.

Rincewind8

I really like that idea. I think it could be very helpful.
I don't think the tire influences the wheelbase, does it? Axle to axle should be all you need.
I would measure the reach horizontally from the middle of the handlebar to the center of the seatpost (or where the horizontal meet the imaginary extension of the center of the seatpost. If the stem is adjustable, then a min. and max measurement.
Further I would add a max. seat rail height, measured from the bottom bracket to the seat rails, when the seatpost is at the max. extension limit.

Wavshrdr

Rake and trail also play greatly into the handling of bicycles as well. Even just changing tires on a more stable design can seriously alter the handling characteristics as well. Then you also need to factor in weight distribution as well and ...

What I am getting at is the average person would have a terrible time factoring in all the variables to get anything really useful out of this type of database other than the physical dimensions of reach and a few other ergonomic type measurements.

v1nce

I am not sure, i reckon it is the first/minimum qualifier in some ways. I have never ever ridden a folder with a significantly short wheelbase that handled well or was as fast as a large wheeled bike. I have never been comfortable on a bike that truly didn't fit me.

As for rake, trail, tires and weight distribution, these things can quite easily be altered, different handlebars, adjusting your saddle etc. The variables i want to know can (almost) not be changed in any convenient way hence i think they are very important to know before buying any bike, especially a folder. It seems one thing almost all cheap and substandard folders have in common is a short wheelbase and sometimes a useless geometry.

Wavshrdr

I don't think wheelbase is a major factor unless you go to the extremes. Weight distribution is not that easily changed due to the fact that YOU the rider are the biggest mass (usually) on the bike. Changing handlebars on folders can create all kinds of other issues especially on bikes like the Bromptons. Take a good bike and just by changing tires can transform it into a pig yet the wheelbase would stay the same.

Obviously with shorter wheelbases there can be inherent issues because of weight distribution because of there short coupled nature but most people can't tell the difference between a 39" wheelbase and a 42" wheelbase. Also through in the fact that some frames are not as rigid and that can be another issue with handling.

My point is to not get too hung up on one particular measurements as bikes can have identical wheelbases but have VASTLY different handling charactersistics. Even the same bike can dramatically change the handling but changing the weight distribution. Unload the weight from the front wheel (all other things being equal) and it dramatically changes the feel of the bike and can make the front wheel wash out very easily in turns. Two bike with the same wheelbase but different rake and trail will have very different handling characteristics but you might wrongly assume that because the wheelbase is the they same that they will be similar.

It may be nice to have some of this info but I personally won't place too much importance on it. Same goes for personal reports. I might consider the bike "responsive" and you might consider it "nervous". It is often just a matter of perspective. I also tend to put more emphasis on people that are similar to my size as well when considering ride reports. Lighter riders might not see the effects that I do because of physical size differences.

A perfect example of this was my Dahon SpeedPro. For me it was a miserable bike most of the time but lighter riders loved it. I constantly had problems with spoke tension. The front Pantour hub needed a different elastomer and lots of other issues that were evident when I rode it. Others were quite happy but bigger guys had problems.

Edd

Wavshrdr what you are saying makes sense about dimensions, even wheel size is not simple as the Bromptom wheel with tyre is not much smaller than the birdy, and tyres, on all wheels, have different profiles, as well.

Edd

v1nce

Yeah that all makes good sense, thanks for that insight Wav. I guess for me these measurements are pretty valuable because i am sortoff an 'average rider' neither large nor small, neither a speed freak or granny, skinny or husky, young or old etc. Additonally unfortunately one can rarely asses the riding characteristics of many if any different folders up front, so having some measurents (especially if you know what works for you from other rides) can be a good first step in making an informed choice. Combine measurements with reviews and asking a lot of questions and i think one/a newbie is a lot more likely to avoid a folder bike that is ill suited for them and hence potentially ruin your view of folders for ever.

Lastly, unfortunately quite a few (cheap/low quality) folder manufacturers Do go to extremes when it concerns their bikes. It seems like the 'smaller, lighter, cutesy' aspects blind them and they forget that ride characterisics can be greatly affected by reducing the wheel base by 1 to 5 inches.
I have just come across so many cheap and terrible (folder) bikes and next to the components (which could have been changed in theory) it was usually the short wheelbase that fouled me up bigtime. And there was no reprieve for that...

clayface

My old folder is 95 cm in wheelbase, which can be considered short by other standards. However, and thanks to this, I have an ace bike that filters through stationary traffic like no other and folds compactly enough to fit in the back of a small car.

v1nce

Interesting. So what is considered 'normal' or for todays folding standard?

Chop!

What is your older folder? Do I have one on my list? If not can you let me have some pics & info please?
I thank you!

clayface

Mine is the green German Victoria fron the early 70's (it's already featured in your list) But I've borowed some more pics from the German Ebay for you if you like them. Italian 20" wheeled Atala and 24" wheeled Garelli and a German Mars with a 2-speed Torpedo-Duomatic hub. Not sure about the Atala, but the two others are from the 70's according to the descriptions.

clayface

...and the Mars

v1nce

Cool to see another doumatic, i got the impression that they were quite rare outside the Netherlands. Even rarer is the 'Automatic'.

@ Chop, any chance you could give me the wheelbase of your GoBike, i do not think i can get it of anyone else!

Chop!

Thanks Roberto!

I had trouble seeing the thumbnails (ZoneAlarm blocks them, turned off ZoneAlarm & presto hey! They came back, Phew!)
I've got to try to figure out why this happens, I've got the Bike Forums as a trusted site, yet it still blocks the attachments GGGGRRRR!

Chop!

No problems, will probably do all my bikes at the same time (before tomorrow's Swindon Smallwheels ride)
Then I can send you the wheelbases for my GoBike, Brompton, Strida and Moulton ;o)

v1nce

Hey, that'd be excellent! I'd appreciate it! Have a great ride.

Chop!

After investigations here are my results........

The first figure is wheel spindles centre to centre, the second is the distance from the centre of the seat post to centre of bars

Brompton :- 104 64
GoBike :- 107 69
Strida :- 91 61 (to seat centre, as there is no seat post)
Moulton :- 109 71 (early rivet-framed non-seperating 'F type')

Hope these help.

v1nce

Thanks a lot! That is both informative and sortoff impressive. It would seem the better designed/well though out brands that you happen to own all have pretty long wheelbases. Moulton sure knew what he was doing 4 decades ago.

I am guessing that the wheelbases of cheapo/old folders will be much shorter most times.

v1nce

Rincewind8 send me this:

My Downtube VIIIFS has a whelbase of 108cm and originally had a reach of 60cm. I modified it and now it has a reach of 70cm.

108! I am happy about that as i might own a DT one day! Nice.

Thanks man!