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Swingarm full range of motion

954 Views 19 Replies 5 Participants Last post by  BlitzSchnell
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Does anyone know what the full range of motion of the swing arm is on a 2015 fully stock Classic. From hanging fully extended on that Bursig stand … to fully compressed and bottomed out ….. what’s the travel distance … or where I can go to determine this measurement. How far up will the wheel travel ? Cheers ……………….. Blitz
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I found this in a German forum (auto-translated), maybe helps:

“- I have measured the steering factor (spring travel/damper stroke) again (several times and with greater effort) and come to approx. 3,1. So far, I had written about 3.36, which I hereby revise with remorse. 1 cm stroke of the damper thus corresponds to about 3.1 cm change in height of the saddle, measured from the wheel axle vertically upwards to the lower edge of the saddle. It was measured with the Bilstein spring strut with removed spring. The stroke of the leg to stop buffer is 30.4 mm, when using this stroke, the rear height (verpenal axis to saddle lower edge) changes by a good 94 mm.”

See if you find out more there with auto-translate.

I just measured my bike (on center stand, so rear wheel off the ground).
At 5“=125mm movement of the wheel, I‘d have contact of my hugger with the underseat!

So, if the rear shock really travels the stated 4.7”=120mm, and there’s a 3.1 leverage factor, then… what?!?
Now I’m confused. Either the shock doesn’t use its full extention (what’s the point of that then), or something else is off with this math. Good thing I’m not an engineer.

Now I try my common sense method: Maybe, just maybe, the stated 4.7”/120 mm is actually measured in the rear, (and the shock itself therefore moves only 120mm/3.1, therefore 38.7mm or 1.55”)? That sounds a lot more like the numbers of the guy above.
Thank you Norbi and Gene … I’m pretty sure the shape I have in mind for Donner’s Yoke will be perfect … I was allowing for just under 6” so I’m pretty sure it will work just fine … Im building the yoke in the morning and I plan to road test this new addition before the coming week is out …. then I’ll put together a more complete story with picts on “My Exhaust Pipe and Bobber Build” so you get a better idea about this entire project and where this info fits in. Thank you for your help…. If Donner trails or trailers as well as he’s looking this project is going to be better than I could have imagined, second coat (final) of the urethane bed liner goes on Sunday … final assembly 1st part of next week, road test on Wednesday weather permitting … Again thank you both …. Blitz
🤞🏻………. Norbi …. Wow is so cool to have a translation from the source …. Thanks Mate …………
Suspension travel is listed as 4.7". I'd assume that is at the rear axle. You could remove the shock and see what the potential travel of the swing arm measures as it will be much more, but the shock will limit the up and down stroke to 4.7" of travel.
Thanks @GapRunr … that’s what I’m working with … Blitz … I allowed for about 5+ so I’m good with the 4.7. 👍🏻
Not so much about the info you are seeking Blitz but may I make a point for the future ? You are speaking of wheel travel "not" suspension nor swingarm travel. This might only be of import when fitting shocks (shock) and figuring spring rates (because of mounting angles) but we should not be confusing some of the Newbee's or go off in the wrong direction next time we discuss suspension and set up. No offence intended as what you were asking was totally valid and made sense in the context it was asked. I've just seen the term used this way before in reference to set-up so this is why I butted in.

Never a problem @rich46 ….. I fully understand the context, content and end result of 4.7 ……. Thank you for clarification as it can be confusing … I was trying to get an idea of how high the swing arm could go under extreme conditions … I'm installing a trailer with a yoke that bolts to the frame of the motorcycle and I want to make sure the yoke and the swing arm never come in contact …. It’s accomplished now …and I appreciate your follow up … BeWell … StayUpOn2 Mate …Blitz
I thought that's what was going on my comment was more about the neophytes than you. When we just get in to all this it's easy to get lost on the phrasing and loose touch. By the way you are a brave fellow. I've always been afraid to tow trailers (I'm even afraid to tow behind my CanAm Spyder ( my wife calls it my Tribycle)) so my hat is off to you mate.
Hey @rich46 … as I built this trailer (Donner) from scratch … my trust level is high. This will be my third single wheel unit and I’ve had one other two wheeled unit. None of them ever offered me any issues as a low speed transport of BS I didn’t want to hang, strap, bolt-on or drape over my bike. I’ve done that and it turns your sporty bike into a tank. You can sight see but you can’t run the curves like I like too. With Donner the end game is the ability to comfortably carry everything I want to drag along and then when I arrive (where-ever) to be able to quickly shed the cargo crap and find myself riding my beautiful sport bike and not my moving van … what ever riding adventures and sight seeing there is to do I can leave the bags and support system behind … the key is keeping the trailer narrower than the width of the motel door …. A one wheel unit can act like a wheel barrow and go right into your room with you.
I understand your reluctance mate … you need to pull one for a bit to realize … if it’s a good build, low center of gravity, good tires etc…. You will forget it’s even back there …. P.S. …Your trike is better suited to a two wheeled version, the motel trick probably won’t work for you on your Tribycle. Cheers …… BeWell and StayUpOn2 ………. Cali is a gorgeous place to ride the coast line all the way into Canada and beyond …….. Ride Hard Happy and fast ! …………. Blitz
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Blitz; when you have time send us some pics. Highway 1 up the coast is truly a once in a life time ride. One summer between jobs I rode from San Francisco to the ferry in Washington , up Vancouver Island .over to Prince Rupert and on to Cold Foot where after talking to a trucker I gave up going any farther. My plan was to ride to Dead Horse stick a toe in the water there and go home. I chickened out after talking to a trucker who reminded me that in Alaska September was late in the year and I might end up staying in Dead Horse for 6 months. That ride along those coast lines was a one off ride that I'll always recall. Cheers
What a ride … truly a ride of a life time Rich. That’s something you’ll carry with a smile in your heart the rest of your life my friend. Now go South ..Baja ?….. NO WAY I’d take a trip to anywhere where it colder than where I am however up the CaliCoast would be the exception ………………. Better Get going before it falls off …………Blitz
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Wow, what a group, 👍🏻 I’m a lucky fella to have found such a bunch …. with or without swingarms ……………………… Cheers one and all ! …………Blitz
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