a arms

[Hmf Ds450]

if i get wider a arms is it bad to get leave stock width of axle or do i need to get a wider axle as well

[joeyds450x]

Originally posted by Hmf Ds450
if i get wider a arms is it bad to get leave stock width of axle or do i need to get a wider axle as well

i left my stock axle on for a couple months after i got my wider a arms it worked fine

[florentino]

Originally posted by Hmf Ds450
if i get wider a arms is it bad to get leave stock width of axle or do i need to get a wider axle as well

the stock its perfect . i got rear spacers 1.5 on the rears .. and 3plus 2 rims on the front bke its 48 inches wide .. and thats all i need.. 18 inch tires help on the rear alot..
but for a really ruff track you dont need to be wider..

what kind of riding are you into?

[Hmf Ds450]

lots of track and some trails, and how much do wheel spacers cost and do they make your quad weaker

[TNT]

In theory Florentino is correct the quad has been designed according to its wheel base, widths, and other geometry to revolve around the center of gravity (CG)) perfect or optimistically. The 08 did not come w/ long travel arms like the 09 MX XC models I believe, so the designed philosophy(loads on the frame) has changed. That’s why imo these race teams that put long travel arms and axles on an aluminum 08 frame have problems(it was not designed for it), or that don't distrubute the load properly. Picture the rear wheels and the front wheels as four weights that rotate around the CG and induce load on the frame. A load(or moment) is a force(at the tires) times a distance to the CG. The more you can keep this system of forces in balance, or it's really a counter balance the frame counter acts to make all the loads zero or cancell each other out, the less stress on the frame and the better handling qualities. Make sense?..there is some out of balance tolerance built in the frame but not much on aluminum since it's not as good as steel in bending. Keep your front and rear wheel widths within an inch of each other especially on the 08's, a lot will depend on the rider.

The wheel spacers are not the best, especially on a aluminum hollow axle they will induce unwanted internal stresses on the axle as they move and bend, but unless you are a pro I would not be too concerned, again assess your riding level to determine if you need an after market axle.

[TNT]

opps :D

[Blizzard24]

The 08 and 09 frames are identical TNT, there is no difference so going with long travel arms on an 08 is doing the same thing as the 09 with the exception of the upper a arm braces that can be upgraded with either the BRP parts or a company such as ATVFourplay.

The axles on all the DS450's are hollow steel, not aluminum. While the 09's are adjustable, the 08's are not.

I dont want to start a fight, but please make sure your facts are right before you post.

[TNT]

Well your wrong Blizzard definitely the loads will change..Unless someone has seen all the frame engineering and loads model, I hope there are 09 differences nobody knows about but I know, like changing hucks(shear heads to tension) or material alloys, the way this is designed on CATIA and NASTRAN the loads WILL change w/lt arms no doubt about it.....Just because you don't see geometry change does not mean Engineering or design did not change, geometry is only part of the design, actually a small part. I'd really like to see where your getting your frame facts from?


I do this for a career I know and I am stating fact. My point is keep the loads in balance it will help the frame believe it or not I don't care, your frame but the race teams(talk to EPIC/Warnett I have)are having problems, you choose. . Again unless some Engineer has reviewed all the 08/09 material alloys, fasteners, etc, it's all hearsay and rumors that there are no differences. My guess is nobody outside BRP has access to the drawing's or models(race teams don't I asked) so hearsay and knowing that there are 08 problems with the frame I would hope were resolved in 09. Race team frames drifted down and they loss ride height. Bending in the frame and I know where and why. According to the race team it was the lt after market arm geometry on a 08 x model that caused the problem.

I messed up on the axle typo meant steel it was early in the am, I think I am entitled to a typo that dont matter....Steel or aluminum don't matter!! I did state fact, spacers will create internal stresses it's just a matter of time before failure. A hollow steel or aluminum axle can be designed to be the same strength material don't matter hollow axle with spacers not the best=fact! I know again I do this daily and for the past 25 years.

No fight here just be careful calling what I post as not factual and if you want to challange it back it up with technical facts and reasoning.

[TNT]

Anyone interested in the mathematics behind why changing to long travel arms creates more stress on the frame I will be glad to show as soon as things slow down a little at work....You will see why the lower arm to the frame joint takes the majority of the load the upper takes very little, and why the race teams are putting in steel cross members on the 08 frames to counter act it. Let me know otherwise I won't waste my time it's pretty complicated and hard to put on a post.

If your using spacers on the inside make sure you torque your nuts with an impact and get them as tight as possible.

[Blizzard24]

I am not questioning your load theories... you are giving manufacturers too much credit around changing and retooling assembly lines... this would not be cost effective to do every single year a slight modification arose around a quad.

Please show us (or at least me) proof the frames changed, and what specifically was changed.
The burden of proof is on you here, not me. You came on here stating they changed the frame to meet the stresses of the longer a arms. Please back this up with proof, not your theory of BRP engineers secretly redesigning the frames.

Wouldnt you think if they redesigned their frames they would advertise this? This would show they were taking a weaker product and making it better therefore making people that may have been turned away from the DS due to these "Frame issues" more likely to purchase another "Stronger" DS450?

They advertised they upgraded the frame straps on the DS450X MX model due to the thinner straps not handling the additional leverage created. They advertised all the updates from the 08 to 09 models and nowhere did they menton improving the frame in ANY way.

Again, show us this proof of a stronger frame... please.

[TNT]

If you read up I never said I had proof BRP made design changes to the frame, no more than you do or anyone, and no if I were BRP I would not advertise a problem I fixed with a small group of national pros….Even steel frames bend(why they are gusseted) and that has to do with all the different after market arms and swings/ riders/ that have been assembled on quads without the proper engineering analysis. You can't blame BRP for that nor can they solve that. Yes I am assuming changes occurred in 09 to help the quads frame be more "race ready" than before with new +2 arms and 50" axles w/spacers, which can change the load case significantly on the frame, arms, and axle. I'd hope BRP is not that stupid to add the extra forward and rear widths to their 09 stock quads and do nothing about it. The CEO would hit the ceiling with warrantee claims to pay and lose money. Aluminum frame technology is relatively new, BRP does not offer the frame segments that are fastened by huck bolts, reason being imo that replacing the fasteners requires engineering and a skilled mechanic. So the alumium/huck bolt/collar technology here is sensitive to load change.

I was curious so I went and looked at an 08 and 09 MX quad today side by side and I did not see any frame geometry changes on the surface, but the gage thickness or alloy of the forward cross over beams below the tank may have changed or a fastener load type change could have occured for all we know we can't see on the surface even without changing part numbers…that’s the beam EPIC is replacing with steel which may create more problems. I did notice some material changes to the spindle and the arm geometry has been redesigned to take and distribute the load to the frame differently, so that may be our answer, to not have to disturbed the frame assembly line too much. In the 08 frame design typically a margin or factor of safety is added to "pad" up the gage(thickness), but at the same time weight is a concern, so like I said about a design loads tolerance being there. My guess is that margin showed good still by taking the 09 arm geometry and redistributing the load to the lower frame clevis and pin in tension primarily.

Most don't have access to BRP dwgs so sometimes we just have to realize how ridiculous it would be to take on 20% more load in the mist of 08 frame failures and do nothing in 09 to rectify the problem. If that were the case as frame twisting continues to occur in 09 BRP develops an undesirable reputation loss in sales and revenue. I, you, BRP and every can-am owner does not want that. Key here is that the factory has added steel arms that will take the load of the majority, that is optimized on CATIA and NASTRAN....I would recommend for most to stay with the 09 factory arms in the future and don't take it upon yourself to reengineer the set-up.

This topic has deviated from a question about widening arms and wheel spacers to opinions on BRP creditability. Yes I have a lot of respect for the BRP Engineer's there job is not easy, after all we are talking about a company that Engieers some on the best aircraft, street, water, on and off road vehicles in the world.

I think I answered the HMF's question well….For 08's it's best to keep the front and back widths close to the same and avoid wheel spacers if possible.

The season starts soon with national pro's on 09 frames, let's hope I am correct the frame issues have been resolved. :D

or it could be the fact that they use rivets to hold the whole bike together? no other atv has ever had a problem with the frame by putting a lt front end on it

[ProspectorJim]

The ds doesn't have frame issues, it never has. The early rumors of pros breaking frames were false if I remember correctly. If somebody's going to break the Ds's frame its going to be the pro's, who have lt front ends as well. The only part they may have strengthened would be the upper a-arm mounting brackets. Atv 4play offered strengthened mounting brackets before the 09's came out ,so it may have been a problem with lt set ups.

121pacheco, the frame isn't riveted together, they're lock-bolts similar to the kind used in airplanes.

[OzLinc]

Originally posted by ProspectorJim
The only part they may have strengthened would be the upper a-arm mounting brackets. Atv 4play offered strengthened mounting brackets before the 09's came out ,so it may have been a problem with lt set ups.


Yes the '09 frame is different and strengthened at the front.

[TNT]

Originally posted by 121pacheco
or it could be the fact that they use rivets to hold the whole bike together? no other atv has ever had a problem with the frame by putting a lt front end on it

Let me try and explain this better. Anytime you change the geometry of anything, don't care if it's a load bearing wall in your house, a load bearing frame member on your car, or the arm geometry on your quad, you change the loading on the entire structure. Say you change the arm geometry and the way the load gets distributed to the frame outside of the way it was designed, and lets say in our example that change gets reacted at the frame beam right below the tank and causes the frame to sag or twist, or, lets go to a steel frame where we typically have to gusset the junctions. Same with load walls in your house, you don't put a header in right you can get cracks somewhere else. All of the steel frames I have seen need gusseting for this reason.

The huck bolt BRP uses is stronger, much, much, stronger than a rivet. It's much stronger than a high grade steel nut and bolt grade A and much stronger than a weld. Reason being is that it is installed in a interference hole and with a gun that pulls the stack up together and it's stand alone strenght is high....Here is a link to one....

http://www.bluepneumatic.com/blog/tag/huck-bolt-tool

What happens is a gun grabs a hold of that shank blind(from one side) sticking out and pulls it through until it breaks at a certain load, a collar is also installed....In this video this guy is just demo'ing not using a close tolerance interference hole it's normally installed in. Problem is they are permanent there is no nut to unscrew or come loose you have to drill them out, enlarge the hole to get the interference fit for the next bigger huck bolt. That can cause problems putting a bigger huck bolt next to smaller or around others on the frame that are smaller. The bigger will take on more load and may now be too close to edge and shear out. Thats why I guess BRP does not offer replacement frame members that are huck bolted together, you need and Engineer to design a repair, otherwise dangerous and a liability issue.

Here is Nastran FEA(Finite Element Analysis) model click on the pic in the upper rh corner....Looks like a part a bearing fits through and thats where the load comes in like arms attached to the frame and heims.

http://en.wikipedia.org/wiki/NASTRAN

This is what I do for a living and how your DS frame was designed. Look at the color codes on right and the part and see the load there. See all the nodes in the model, well we can pick a node and find out the shear, tensile, compression loads anywhere on the frame. That way we can design other parts to interact with each other and determine how thick, what material, alloy, size of fasteners, etc....This model is based on loads that were put in. In the case of the quad the OEM's use stress-strain gages all over the quad to determine the load, mainly input at the tires, then put in the computer or FEA model. So as you can see, if I change the arm geometry from it's original design, this model is no langer valid and problems can occur.

Pro's will be pro's and only frame issue I heard of were from pro's. This happens to steel frames and all quads from pro's, the DS is no exception. IMO in the race for the true "Pro Race Ready" quad the OEM's will produce stronger and stronger quads until their quads can compete stock in the pro and amature A/pro-am Production classes. Some this season in the A, Pro-Am class are doing that with the KTM, but it's comes with a high price and we have yet to see if it's frame holds together and the rest of the quad. We can only speculate no data.

Hope that clears things up a little. IMO if I were you 08 guys now, and I know you had no choice but after market prior to the 09 release, but now your best shot is 09 arms that were designed to the frame w/the new parts. I would not use the stock axle w/spacers, I go to a Dominator 11 or somethng else with no spacers. 09 owners replace the arms with BRP products when they wear.

:D