Kona Frame Geometry Changes - Old V New

[Afflicted.John]

Cut a long story short I have had a '97 Giant Team MCM sitting in my shed. Doing nothing. It doesn't inspire me very much and the whole "wow it's covered in XTR" I regret. The alternative was a brand new Kona Explosif in 1998 and I cannot help thinking that if I had brought that instead I would have been riding a lot more in the last decade.

But anyway, I am getting older and really wanted to spend some time doing something that I loved very much as a kid, and nothing brought me more joy than my Kona Lave Dome. So I'd like to get back into the habit and am after a steel Kona.

I have seen the 2010 Kona Blink up for grabs @ Merlin for a reasonable price, but having read comments on this forum about the quality of the chromoly, I wonder whether a second had steel frame might be better? I figure I should be able to sell my carbon MCM for at least the price of a good steel frame?

Also, if Kona have not changed their geometry, then is the difference in recent catalogues purely down to the longer travel forks?

I have virtually replaced the MCM drive drain, reusing what was good but the XTR mechs weren't long for the world when I bought it and so I have put a mix of 9 speed SRAM X7/9 and an XT Hollowtech II bb and crank on it. Apart from that, the XC700 SE forks still work although I would be after longer travel ones I think... Disc brakes don't bother me...I was winning races on cantilevers and so my XTR V's will still do me just fine I think...

So what would you do? Kona Blink as new.....or a second hand Kileaua/Explosif frame and do a swap with my current components?

Also, any offers for the Giant frame would be gratefully received. I'll post some pictures if requested. Thanks!

 

[Gruff]

Sell the MCM & look for an old Kona

 

[Afflicted.John]

What's the maximum travel fork you can run a classic Kona on? Test rode a Ragley earlier which was pretty nice but it had 140mm forks - does the geometry on these change only because of the long fork? Or would a Ragley with 80mm forks behave pretty much like a classic Kona?

 

[lumos2000]

kona changed the geometry in 94 to use 80mm bouncy forks, 410 a/c.

 

[Anthony]

What's the maximum travel fork you can run a classic Kona on? Test rode a Ragley earlier which was pretty nice but it had 140mm forks - does the geometry on these change only because of the long fork? Or would a Ragley with 80mm forks behave pretty much like a classic Kona?

A steel Ragley weighs about two and a half tons and is designed for a completely different purpose to a 1998 Explosif, but funnily enough the geometry of the frame is quite similar.

Kona didn't change their frame geometry from 1994 to 2009, instead they just used shorter stems to compensate for the longer forks and still keep the same sharp handling/steering. This is a 96 Explosif with a 100mm Fox Float and an 80mm stem and it has excellently sharp handling. I wouldn't fancy using this fork with a 120mm stem though, I expect that would be dire.

If I had a 120mm fork, I'd be up for trying it with a 60mm stem. I expect that would work quite nicely too, but I can't say for sure whether the formula works as well when stems get really short. I think that's roughly what Brant Richards does though.

 

[Afflicted.John]

Damn it! THAT WAS THE BIKE I SHOULD HAVE BOUGHT!!

Lucky sod... ;-)

 

[Afflicted.John]

If I had a 120mm fork, I'd be up for trying it with a 60mm stem. I expect that would work quite nicely too, but I can't say for sure whether the formula works as well when stems get really short. I think that's roughly what Brant Richards does though.

What size Explosif is that?

 

[Anthony]

If I had a 120mm fork, I'd be up for trying it with a 60mm stem. I expect that would work quite nicely too, but I can't say for sure whether the formula works as well when stems get really short. I think that's roughly what Brant Richards does though.

What size Explosif is that?

It's a size 18, which is actually a bit too big for me, as you can see from the seat height - but with an 80mm stem, it's effectively the same size as my size 16 Explosif with 100mm stem and 80mm SID. If I had a 120mm fork, I would fit it to a size 19 frame, so that a 60mm stem would make that the same size as the 16 too.

 

[Afflicted.John]

Hmmmm....so a 90mm stem should do me fine on a 19" Kona which is what I am aiming for (yippee...Race Face!) aiming for a 100mm fork.

I remember running a 135mm on my 18" Lave Dome.

 

[Anthony]

The formula I work to on a retro frame is 180mm total for the travel plus stem, so a 90mm stem and 100mm fork wouldn't be far out. Bear in mind though that this is an over-simplification, as any exceptional amount of sweep in the bars will effectively reduce the length of the stem.

The 180 comes from a stem of 120mm on a rigid bike and the 41cm a-c rigid fork being equivalent to a sagged 60mm fork. Those 135 stems and longer always did deaden the steering, but designers still used them because if that is the riding length/posture you need, then it may be preferable to achieve it that way than with a longer wheelbase, which also deadens the steering. Some high-end makes (but not Kona) employed a steeper head angle for the big sizes, which counteracts the deadening effect of a long stem and long top tube, without extending the wheelbase by as much as you have lengthened the top tube.

But obviously longer forks make for a higher front end and more upright posture anyway, so you no longer need the kind of stretched-out position that 135mm stems were for.