classic proflex geometry

[boro92]

Hi all,

I've checked with retrobikes.co.uk, and they recommended to peep in here!  Did not know about such a knowledge house and excellent resource for these great bikes

Ever since I was in early grade school, I was infatuated with the bike.  Fast forward to many years later, I finally own a fine example of a 656.  Right now, I'm curious and would like to know a little more.  Specifically, I've search around but cannot find any geometry figures on proflexes.
To be more precise, does anyone know the head tube/seat tube angles on these bikes?

I wonder if the frames were designed differently than the norm to compensate for the "reverse rake" of the Girvin forks. Would really love to know!

[shovelon]

No, I don't think they use different geometries than standard. In fact the linkage forks were sold individually too as aftermarket accessories.

The reverse rake you are referring to is what I call the "Dreaded J-Path". Works OK for me with short travel Vector forks, but longer travel Crosslinks tuck under too much for me, shortening the wheelbase on compression.

Your bike should be able to handle a 3 or 4 inch slider fork if yours goes south someday.

Terry

[boro92]

No, I don't think they use different geometries than standard. In fact the linkage forks were sold individually too as aftermarket accessories.

The reverse rake you are referring to is what I call the "Dreaded J-Path". Works OK for me with short travel Vector forks, but longer travel Crosslinks tuck under too much for me, shortening the wheelbase on compression.

Your bike should be able to handle a 3 or 4 inch slider fork if yours goes south someday.

Terry

Thank you!  Good to know.

You're exactly right.  I eventually found that the bikes are classic 71ht 73st angles with 38 rake.  A fairly standard affair!
Didn't know about the crosslink issue.  I have to say that the vector works great for me (although with my present elastomers, I probably only get 1' of travel) likely due to the small amount of travel as you mentioned! 

[kiwi]

Forum member Dave Twede used to have a page on proflex geometries but it was an old geocities one which has gone....

[kiwi]

well well look what i found

and an even older version

[shovelon]

well well look what i found

and an even older version

Nice Find!

Terry