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Discussion Starter · #1 ·
The Alt-Rider Upper and Lower crash bars are the best available for the Africa Twin (in my opinion). However, there is a very serious engineering flaw with the reinforcement bars (optional third piece that connects Upper bars to Lower bars on each side). Once connected, they cause a horrible high frequency vibration between 3800 and 4200 RPM. It is so bad, it will probably cause damage to the engine and frame welds over an extended period of time. The problem is that they turn the entire crash bar system into a huge tuning fork that adds harmonic vibrations at the RPM range previously mentioned. I'm going to try adding strips of weight to the reinforcement bars to act as a damper. I hope this works; Otherwise, avoid the reinforcing bars option.
 

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Interesting. Have you brought it to the attention of Alt Rider? If so, what was their response? Did they offer any possible suggestions?
 

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I received the bars today, installed them and discovered the issue within the last 4 hours. I plan on contacting them tomorrow. I'll update the post when I hear from them.
Cool! They are an excellent company to deal with and I am sure they will appreciate the feedback. It may give them some thoughts for a design change in a future revision.
 

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I have not noticed this either.

Are you certain these are torqued down properly?

My only complaint about the brace bars is they damage the upper and lower powdercoating when you tighten these down or even fit them.

The cast pieces are super sharp and cut right into the paint. So if you make a mistake on placement you're pretty much boned.
 

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Discussion Starter · #11 ·
They're definitely fit and torqued properly. The ride is smooth as silk without them and extremely noticeable vibrations (between 3800 and 4200 RPM) once they're added. Obviously, you need to be riding on a fairly smooth paved road or you may not notice it as much. Alt-Rider is looking into this and said they would try to get back to me within a week or so. I have the silver bars so there is no scratching issue.
 

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Very interested to hear with the root cause is or if there is a problem. Was ready to ditch my Touratechs in favor of the Altrider, but will wait to hear if there are more cases of this or this gets resolved...

Keep us posted!
 

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Discussion Starter · #14 ·
I installed the ALT rider crash bars this past week and have the vibration at the same RPMs
Hey Sparky, if you have time you should let Bruce ([email protected]) at Alt-Rider know about it. I gave him a full description of the issue and they're very concerned and doing testing to find a solution. The more people they hear from may expedite their solution. I am personally trying to make a custom set of rubber mounts to isolate the harmonic vibrations and I may also try filling the tubes with lead shot to act as a dampener. I'm not thrilled about either of my ideas...I hope Alt-Rider comes up with something better.
 

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Discussion Starter · #15 ·
Vibration Problem is ONLY With Reinforcement Bars

Since this thread is getting a little deep now, I just want to confirm that the vibration problem is ONLY with the "Reinforcement Bars" that connect the uppers to the lowers. This is a 3rd optional set of bars that can be added after the initial install of the uppers and lowers. I still highly recommend the uppers and lowers which can be purchased separately. There are no vibrations with the uppers and lowers...Only after installing the reinforcement bars which connect the uppers to the lowers.
 

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Discussion Starter · #17 ·
So did they say that they noticed this during their testing? If they cannot replicate then they cannot fix...
Still waiting to hear back...Apparently, their Africa Twin is being used by their President on a Colorado journey so the testing is yet to come. I'm sure it's a problem with all Africa Twins using the reinforcement bars. I would suggest the 2 gentlemen that haven't noticed the problem do a more careful review at the RPM's I noted both with the bars and without. Extended exposure (hundreds of hours) to vibrations like these can cause very serious structural issues.
 

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Still waiting to hear back...Apparently, their Africa Twin is being used by their President on a Colorado journey so the testing is yet to come. I'm sure it's a problem with all Africa Twins using the reinforcement bars. I would suggest the 2 gentlemen that haven't noticed the problem do a more careful review at the RPM's I noted both with the bars and without. Extended exposure (hundreds of hours) to vibrations like these can cause very serious structural issues.
So have you removed the reinforcement bars for now?
 

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Discussion Starter · #19 ·
So have you removed the reinforcement bars for now?
Yes, they're off for now...I'm going to try to make some hard rubber mounts to isolate the bars but that pretty much makes them 50% "eye candy" and 50% structural at best because they won't have the very stiff connection points. I am also toying with the idea of filling the hollow tubes with some #11 lead shot in an attempt to "dampen" them. I estimate it would add about 6 pounds of weight (3 right and 3 left). I've been using Alt-Rider crash bars for years on several of my previous bikes and this is the first issue I've ever had. It's also the first time there has been a "third component" that attaches 2 other pieces together like this.
 
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