SuzukiSavage.com - Strength of modified swing arm

John in Kalifornia

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Strength of modified swing arm
08/25/12 at 00:28:24

Hi All,

Today we modified the swing arm for the bigger diameter tire. I'm using a Duro 308 Pirelli Universal replica in a 400 by 18 size. The overall diameter is 26 3/8 inches. It would fit barely with the axle adjustment all the way back but that left no room for chain stretch adjustment or allowance for centrifugal force. In other words if one wanted to actually ride the bike the tire would rub on the swing arm.

Has anybody who actually ridden a bike with the modified swing arm any opinions on whether it is strong enough? I know the Savage is more of a bike for poseurs than actual hard core canyon racers but still....

Maybe it needs some reinforcement. I dunno. The plate that we welded on is boxed all the way around with good weld penetration.

John in Kalifornia

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teabowl13

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Re: Strength of modified swing arm
Reply #1 - 08/25/12 at 07:31:56

I'm no expert in this area at all, but I assume that most of the strength of the stock brace comes from the straight, vertical portion at the front, combined with the fact that it is triangulated towards the back.
The way that you and RYCA modified the swingarm keeps both of these parts in tact. It appears also that the new section that you welded in is much thicker steel than the stock bracing material, which seems surprisingly thin to me for the job it's doing.

I'd say your brace is at least as strong as the stock swingarm if not a little stiffer, but I doubt seriously that it's any less sturdy.

Of course most Savage riders are not canyon racing their bikes, but none the less, after all the reading I've done on this forum over the last year, I have never read anyone complain about swingarm failure; even among the RYCA guys.

Put that thing back together and go ride it!

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Oldfeller--FSO

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Re: Strength of modified swing arm
Reply #2 - 08/25/12 at 07:35:23

The swing arm is mild steel pipe and sheet metal, you didn't anneal anything or hurt anything by what you did.

==============

"I know the Savage is more of a bike for poseurs than actual hard core canyon racers but still ...."

I'll leave your education to someone who lives local to you.

Once you get a Savage up into the mountain curves it becomes quite well suited to the environment, great low speed acceleration out of the corners and very good cornering ability.

It is a wonderful bike for sucker trapping newer Harley Sportsters and Glides and such, they can't believe it can flat run away from their 1,200 cc 600 pound behemoths and it can certainly lead them into turns/situations that they can't get out of.

Wink

Fat old fool on a single cylinder grandma sickle, I'll show him !!! eeeek!

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verslagen1

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Re: Strength of modified swing arm
Reply #3 - 08/25/12 at 19:48:08

John in Kalifornia wrote on 08/25/12 at 00:28:24:

I know the Savage is more of a bike for poseurs than actual hard core canyon racers but still....

You expect an answer after that? Angry

Only way to know, test it.

secure one side and hang a weight off the other, do the same to the original. And compare the deflection... if you can measure it.

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justin_o_guy2 Serious Thumper Offline What happened? Posts: 55279 East Texas, 1/2 dallas/la.	Re: Strength of modified swing arm Reply #4 - 08/25/12 at 19:58:55 I gotta get pics of whats left of my pegs,,These bikes will lean into a turn,,if youve got the balls,
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John in Kalifornia Full Member Offline SuzukiSavage.com Rocks! Posts: 127	Re: Strength of modified swing arm Reply #5 - 08/27/12 at 15:40:41 Here’s what it looks like on the bike John in Kalifornia
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irondad01 YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 25 Osceola Mills, PA Gender:	Re: Strength of modified swing arm Reply #6 - 08/27/12 at 16:20:02 You are also still supported by the axle and the pivot bolt at the front. I don't think it can go anywhere. I hope not because I did mine the same way. Carl
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Spamy

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Re: Strength of modified swing arm
Reply #7 - 08/27/12 at 21:57:03

I cut mine out about the same as you did and I havent noticed any problems what so ever.

With the weight of this bike it seems to be completely sufficient.

Ive been riding with several individuals lately on much more sporty bikes than ours and it hasnt felt loose or unpredictable at all while leading those other bikes into corners.

I think because of where the shocks mount its mostly a non issue. If it was a mono-shock type of configuration it may be a different story.

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Pine Serious Thumper Offline SuzukiSavage.com Rocks! Posts: 1694 Mississippi, USA Gender:	Re: Strength of modified swing arm Reply #8 - 08/28/12 at 14:24:45 well dang.. now I am poser.... gues I can always sell it... borrow 10 times that amount and get a non-poser bike. Wait .... weren't the main characters in Wild Hogs all posers on such?
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