PDA

View Full Version : In Reference to Magazine Comments On Handling



ThePhantomRider
09-07-2007, 11:07 AM
As I have read some comments on getting used to the DS handling as it has a different feel than the other 450's a thought came to my head as I discussed steering geometry and design with my father in law who is an engineer for Indycar and suspension and handling expert.

I realized that the reason some testers feel that it works different than the other 450's is that as riders, we have had to work with designs that were not optimal. Think about it, look at the spindle in any race car and you will see what Can-Am was going for in trying to get the pivot axis of the ball joints as close to the centerline of the tire as possible. This gives you more accurate steering imput at all suspension angles. The tire does what is intended, thats pivot, not swing around an axis like every other quad does.

Try this one on for size, look at every thread pertaining to wheel spacers, most everyone who has suspension knowledge says front spacers are a bad idea beacuse not only does it put a load on the spindle, but the further out you push the tire, the less precise the steering becomes. It's the difference between traditional design and correct design. We simply have grown accustom to "acceptable design" as opposed to "correct design" So when riders who have clouded their minds into thinking what is good handling get on the DS and think, wait a minute, the front end is light, but it turns sharp, that doesn't compute, they assume it's wrong. But even the most high dollar setup out there still uses improper geometry.

Add to that the reduced kickback because of the compact spindle, which is made possible by the tire pivoting as opposed to moving around the axis, it takes less steering effort, which takes us back to the reduced size of the spindle. This allows the rider to actually add throttle to get the bike to bite even more and drive out of corners under power as opposed to (Articles in said Dirt Wheels have been on this) racers who have to back off throttle to get the steering to bite more therefore you lose momentum in the corner. You have to change the mentality of what works before you can appreciate proper geometry.

While some get all this, there are those who still think that wrong is right and correct feels wierd, in time they will come around, but for now we have to deal with a magazine like Dirt Wheels not really having a real test for the DS vs. KFX vs. YFZ and them saying the YFZ is still the best (It's a very good quad BTW).....yes they pay the most, but also I go back to being used to somthing....they have had the YFZ for years now, they are used to it which makes for a biased opinion.

Though I'd like their testers and editors to ride in a race car with both types of steering designs represented and, being an alien vehicle, then have them tell me which theory works best, you'd be surprised in how bad they would think the old way works compared to the new.....

TPR

Punk'd
09-07-2007, 01:39 PM
I have the exact same outlook as you with the whole "This handles like crap!" comment made by some people. Im sure it will be weird at first, but when you get a new quad everythings always a little diffrent.

I agree with you that in time people will begin to notice the truth.

ThePhantomRider
09-07-2007, 02:52 PM
I can tell you that I have felt first hand the difference between a setup that is close to what the DS 450 runs and somthing that is more along the line with the other 450's.

A few years ago Epic was working on the DS 650 for Baja applications. When they figured out that the first untapped problem was the fact that the bike was too large for the typical 20-22" tires, they went with 25" tires and 12" rims which really improved the way it attacked whoops.

Since the rims were bigger, they had a custom offset made that pushed the spindle into the wheel and made the pivot much closer to the centerline of the tire....I can tell you that if you ride them back to back it's amazing the improvement, and that still is with the actual design being ordinary.

What Can-Am has done is taken that and moved leaps ahead to take care of a number of overlooked difficencies in current design.

It's just like the waffleheads that think they want the shock all laid out at wild angles when optimal is as perpendicular to the plane of the arm as possible. That reqires lighter springs and valving because the leverage is less and more consistent. Again, look at the front of the Can-Am....almost vertical and plus but bottom resistent.

TPR

TWILES
09-08-2007, 11:14 AM
If it makes you guys feel any better I thought the 450R handled like crap. The front felt toooooo heavy on the ground and too light in the air. I was let down and said that if that was the best they could do I was done so I bought a dirtbike. I bought a blue one and haven't been let down since. I think the problem is that they have gotten too precise and centered all these new 450's around a certain weight and hight person where a 250R and Banshee fit just about eveyone. I'm 6'1 and feel like a giant on the 4 main one's. I doubt I ever buy another one even though I would LOVE to have another sport quad.

ThePhantomRider
09-10-2007, 09:12 AM
I think you are partially right, the 250 did fit a broad spectrum, but again there is a situation where there wasn't much competition for a looonng time. Sure there was the Quadracer and Tecate, but not very long.

Now it's getting like it is and has been for the MX crowd...almost like there is some magical formula which makes a quad feel right. When you bias that with money I don't think you get a clear picture.

Mainly though I was pointing out how we as riders, have grown accustomed to riding ATV's with geomerty you would never consider putting on a road vehicle. Now Can-Am comes along with designs that more properly create proper handling and it confuses people into thinking somthing is not right.

Just wait, you'll see as time goes on, the other manufacturers will follow suit with their geometrys in thier own ways.


TPR

LTR450_#67
09-10-2007, 11:21 AM
TPR I agree with you on most of this, but much of this really isn't all that new....it's just had more R&D and technology put into it. For instance the geometry of the shock angle on the Honda R in the 80's is more straight up and down in comparison to the Quadracers. Honda has always been pretty good about that stuff. Sames goes for attack angle or "Rake" on the front-end, the R has it and the quadracer didn't, which made the Honda superior to the Suzuki. Now to the present... Honda uses similar geometry as the 250R, it's basically just been glorified and is why it is a favorite. Yamaha is in the game blindly but has actually made a pretty decent machine. Hopefully they have taken some notes on what they need to change. Suzuki has come in blind too but not as bad as Yamaha.

As for the Pivot Vs. Swinging action of the steering motion on the front end .....The band-aid is 4-1 offset rims. And don't tell me they don't help. Like I said... band-aid.

Over time the rest will catch up.

ThePhantomRider
09-10-2007, 02:53 PM
Originally posted by LTR450_#67
TPR I agree with you on most of this, but much of this really isn't all that new....it's just had more R&D and technology put into it. For instance the geometry of the shock angle on the Honda R in the 80's is more straight up and down in comparison to the Quadracers. Honda has always been pretty good about that stuff. Sames goes for attack angle or "Rake" on the front-end, the R has it and the quadracer didn't, which made the Honda superior to the Suzuki. Now to the present... Honda uses similar geometry as the 250R, it's basically just been glorified and is why it is a favorite. Yamaha is in the game blindly but has actually made a pretty decent machine. Hopefully they have taken some notes on what they need to change. Suzuki has come in blind too but not as bad as Yamaha.

As for the Pivot Vs. Swinging action of the steering motion on the front end .....The band-aid is 4-1 offset rims. And don't tell me they don't help. Like I said... band-aid.

Over time the rest will catch up.

Oh yeah they really do help and yes it's a band aid. Epic had a custom set of 5-0 offset rims, basically the center was cut out and rewelded to the outside ring, made a huge difference.....

That showed the way to a better design.


TPR

Punk'd
09-19-2007, 01:07 PM
I'm very excited to feel how these handle in comparison to my 450r!

montycarlo
09-19-2007, 08:04 PM
TPR I recived their promo DVD in the mail and watched the whole thing - even stayed awake for it! I remember how they explained the bit about the steering axis but it didn't make complete sense to me until you explained it - Thanks I got it crystal clear!


Maybe it was their French accents that threw me off! :D

ThePhantomRider
09-20-2007, 08:01 AM
No problem.


TPR