Bonneville America Forums Forums Technical Forums Custom Corner Springer front end on an America

I just saw this bike advertised locally to me, and thought you all might find the picture interesting. Apparently its a 2008 America.

Looks to me like its an el-cheapo DNA springer front end and IMHO looks a little long. But good on the owner for giving it a go and successfully getting one on there...

[image]http://img1.classistatic.com/cps/kj/110731/977r2/8253ec_20.jpeg[/image]

now that i do like

Different and just think, no more leaky fork seals.

it looks like ZED's choppa with the bars

what kinda pipes are they?

Those look like stock HD pipes.

I still want to do a leaf spring front end on my bike. Those things are expensive...

Ian are they like the slip-ons that go on baggers?

A COUPLE OF DRINKS AT LUNCH CAN MAKE ME VERY PRODUCTIVE DWIGHT!

Good one, Tom!

yes sir

Yep,that's a nice looking bike

Wonder why he did not go the whole
"hog" and fit the belt conversion?

I know that front end, I wonder how the stem length problem was solved and probably has a big tuning radius so the springer doesn't hit the tank. I have a few ideas how to fix the stem issue but haven't purchased a front end to play with yet.

600 bucks for a Springer from Mid Cities. DNA has a pretty bad reputation I think.

Soo, is it not yesterdays technology that was replaced with something so much better? Or, was the springer replaced by something that was just cheaper?

I don't know the answer just wondering why every engineer from every manufacturer took springer out of the plans so to speak.

I keep thinking about that Harley youtube about this is 1938 technology and we are going to charge you extra for it.

That said, I really like the look of it but it sure ain't Triumph and never was.

There are $300 springers I could use to experiment That are the same in dimension and work fine for a while but lack some of the features of the more expensive brands. Springers work very well in my opinion except they bounce because they lack dampeners. The old girders worked well too and better ones had friction plates on the side that were adjustable for dampening, these worked better. I haven't ridden a springer with a shock yet but I would imagine, if set up right, would work just as well as telescopic forks. I rode a springer bike for many years and loved it, the bounce was fun. With the long springer I could watch my front wheel bounce due to harmonics on the highway!

So, with a twisty bouncy road a springer may not handle it as well as telescoping forks in an emergency? Or, it wouldn't matter. I am just wondering why they were abandoned as a technology. Assuming maybe the rake and trail were not conducive to tight turns and hard leans.

Been around bikes for a long, long time but never owned a springer.

The springers I have ridden do not handle well is the road is bouncy but fine in the twisties on a smooth surface,a bump or 2 has little impact but if there is enough to get the wheel bouncing it could be dangerous.I remember chasing a friend up a rough twisty road and bouncing all the way from the inside of a corner to the outside. But add a properly dampened shock and spring tension adjusted correctly for conditions I don't see why a springer wouldn't work almost as well if not as well as a telescopic front end. I still would like to put a springer on mine but still have not worked out all the issues in my head yet, I think a girder may work better on our bikes than a springer just due to the tree geometry and clearance to the tank.

Got it!

(Strictly bar-hopper or show bike only)

Or this Jesse Rooke design front end (although I'd still like a front brake):

A leaf spring front end would be cool but the angle doesn't look right on the first shot of the one on the Pan.I like the ones on the old Indians.

Seems that is a KIWI front end on that Pan and might just be the rake of the frame that puts it at that angle.

Now if you leveled the leaf out, lowered it a bit and put a fender on top of it, I would like it. let the fender ride up and down on top of the leaf.

Ron, to answer your earlier question that was basically asking if pre-telescopic fork design has been left to history...

Actually, BMW today has had basically an updated "Girder" front end on their K-series motorcycles for a while now...since around 2006.

The advantages of a girder or of a springer design are that their geometry somewhat lessens the effects of front-end "brake-dive", because of their "leading link" setup.

And so, yes, that design is still around.

As far as a springer goes, the axle being ahead of the rocker pivot point actually has the opposite effect of the dive experienced with telescopic forks. The resistance created by the application of the front brake actually raises the front end a little.

The girder intersects a mono shock right? I guess before shocks we used springs thus the springer.

Was just looking and they don't use it on all of the bikes. Clearly its not bad technology just older.

Why would a leaf spring be better than a set of coiled springs I guess would be the next question. I am starting to figure its just a matter of preference and it all works OK>

A girder doesn't have a shock in most cases but like a springer it can. Many girders did have clutches or friction plates on the pivot point that were adjustable very similar to the old style steering dampeners. That sort of worked as a shock in that it created resistance to bouncing.

But the BMW girder has a shock right?

Not familiar with the one Dwight is talking about. The Earls front end is the odd BMW front end I am familiar with but I would imagine it does.

By the way I looked a little and didn't readily find a good shot of the that little clutch I am talking about on some girder front ends. Only good shots I found of that part of a girder were of ones with no dampener.

Odd way to build one but it does resemble a girder.

A lot of thought went into that front end.

Not just any thought, German engineer thought.

Ya know, it kinda looks to me like they designed the suspension part then thought..."Now how do we attach that to the handlebars?"

Yeah, sort of anyway, Ian!

Actually, I think the design principle here was to separate the suspension from the steering mechanism so as to negate, as much as they could, any "Bump Steer".

I'm sure that was the case Dwight but the steering looks like an after thought even though I'm sure it is all part of the intended design.

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parallelogram actuation arms

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I'm sorry Dwight, but I don't speak German. What exactly were you trying to explain (in Hoserese if you will)?