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Posted: January 20th, 2009, 1:22 pm
by dannygraves
my point exactly, excessive vibes are usually a sign of a problem, but it could easily keep running for 10 years like that.
:wink:

Posted: January 20th, 2009, 2:10 pm
by Roostius_Maximus
and break pipes, mounts, loosen bolts.

Posted: January 20th, 2009, 4:41 pm
by 100hp honda
does alunimum vibrate more than steel ?

Posted: January 20th, 2009, 6:02 pm
by dannygraves
aluminum is more rigid, so I'd guess so...

Posted: January 20th, 2009, 8:19 pm
by AlisoBob
Vibration has to do with the material, and frequency at which it naturally excites.

Jet engines have TREMENDOUS vibration, its just at such a high frequency we dont perceive it.

Generally, the heavier and and more elastic some thing is , low lower the frequency it resonates at.

The reverse is also true...

For a vibe free CR500, you want the engine, frame, subframe, exhaust, and everything else to be monolithic.....

Once something starts buzzing.... it all buzzes.

Posted: January 20th, 2009, 9:31 pm
by 100hp honda
AlisoBob wrote:Brit rode all through AZ with a shattered piston, failing tranny, massive and cooling system corrosion.

He never suspected a thing....

:roll:
dont forget dumont or was it glamis?- coolant disapeared somehow and head was hitting the piston, i think he suspect it after a hour or 2 :lol: . im not really making fun of him but its alittle bit funny :lol: :lol:

Posted: January 22nd, 2009, 3:14 am
by asteroid500
there are many high end trippleclamps with interchangable rubber bushings to ajust the chassis dynamics of your bike.
add to that some very soft hand grips that you may need to change every 2nd meeting but are well worth it.

also in 250 production road race bikes we used to shim the motor to the chassis with high tensile shims that realy helped, i will be doing this in my GEN1 build.

or you could just simply put a tea spoon of concrete in your coffee and "HARDEN THE FUCK UP" :twisted:

LMAOA :D

Posted: January 22nd, 2009, 6:28 am
by JBaze
asteroid500 wrote:there are many high end trippleclamps with interchangable rubber bushings to ajust the chassis dynamics of your bike.
add to that some very soft hand grips that you may need to change every 2nd meeting but are well worth it.

also in 250 production road race bikes we used to shim the motor to the chassis with high tensile shims that realy helped, i will be doing this in my GEN1 build.

or you could just simply put a tea spoon of concrete in your coffee and "HARDEN THE FUCK UP" :twisted:

LMAOA :D

I like the last line! :lmao:

Posted: January 22nd, 2009, 7:45 am
by juddy
Has anyone already mentioned balancing the crank V's piston ? Adding weights to crank somehow.Thats what the guy that has built 11 winning 'Finke Desert Race' CR500 engines does,among lots of other shit.

Posted: January 24th, 2009, 9:55 pm
by zorak-2
K here is my input on the vib issue.on my 91 it has the vibes real bad and halfway through a ride my hands are numb :( .i bought the inserts from faast what a waist made no difference put silicone in the bars nothing still had the bad vibes.i have hand gaurds also pro tapers i dont know if that makes difference but nothing has helped.my next step is when i can muster up enough cash motor is coming apart and every bearing will be replaced,crank and rod will be trued and balanced and tack weld so it will not rotate.

in my own opinion i think over the years i think the crank halfs get out of sequince thus causing vibration.i might be wrong but i had a yz125 that the crank got press to gether and it was not true and had the vibes also.so thats just my theary on the subject.

Posted: March 11th, 2009, 10:32 am
by _joshua_

Posted: March 11th, 2009, 12:53 pm
by bulitnv
Another nod for Fastco's Flex Bars. I had them on my last AF and will be putting them on my current AF as well.

They do take several rides to get used to. Several times I was close to yardsale before I began to trust the feel of the flex bars.

Chris

Posted: March 17th, 2009, 10:02 pm
by NightBiker07
i really dont see where the vibe complaints come from. i have never ridden any machine that bothered me as far as vibes go, but then again i grew up riding rattly-as-fuck mini bikes......

Posted: March 19th, 2009, 7:50 am
by mega491
Not sure if someone already suggested it but a cheap and easy thing to try also is a flywheel weight in the heavy range.

If it were me and I were going to be riding in the upper RPM range alot on a 1/2 mile oval I would change the balance factor in the crank. The stock factor is for MX which is alot of off idle thru mid to upper mid RPM and short bursts into the upper range. Consult with a crank expert for accurate info but my guess is a balance factor of around 60% for a single cylinder 2 stroke is the range that smoothes out the higher RPM vibration but will increase the vibes in the lower RPMs. You need to adjust the factor for the "sweet" spot at a higher RPM.

If a bike vibrates badly and equally at all RPMs something is wrong. Possibly out of true. If anyone tapped on the crank to install it or a sprocket, dropped it or something it could be out of true. Some are bad from the factory.

Mega491

GenIII 500
Maicos
& more

Posted: March 19th, 2009, 9:10 am
by hoofarted
just an idea - but has anyone just loosened the rubber handle bar mounts that go thru the upper tripple? I mean not loose to the point where its wobbly - but just enough to allow some flex...The nuts are nylocks so they will not loosen further either.

Posted: March 19th, 2009, 10:32 am
by south central hoon
NightBiker07 wrote:i really dont see where the vibe complaints come from. i have never ridden any machine that bothered me as far as vibes go, but then again i grew up riding rattly-as-fuck mini bikes......
X2....WTF is the big deal?

Posted: March 19th, 2009, 12:39 pm
by ShanMan
...if you own an AC Cobra 427 do you complain that its got a lopey idle and vibrates A LOT on the way from zero-100-zero in 12 seconds? Doubtful! Isn't an AF pretty much the same thing? :roll: :lol:

Posted: March 19th, 2009, 12:44 pm
by dannygraves
x2 :lol:
my stealth chatters my teeth over every bump, but it'll do over a full lateral G... same idea :D
my gen'1 vibes pretty bad, but it being the stupid fast hill shooting bike, I have no intention of doing anything about it.
my gen-3 on the otherhand will be a mellow trail bike and super comfy, so it got a brand new crank.

Posted: March 19th, 2009, 12:45 pm
by ShanMan
ShanMan wrote:...if you own an AC Cobra 427 do you complain that its got a lopey idle and vibrates A LOT on the way from zero-100-zero in 12 seconds? Doubtful! Isn't an AF pretty much the same thing? :roll: :lol:
Nobody I know rides a 500 because of it's civility......it's really all about measuring your dick against guys who ride less displacent...albeit slower bikes, and worse yet, those silk-smooth, Chernoybl-based thumpers! :twisted:

Posted: March 19th, 2009, 12:45 pm
by AlisoBob
This belongs in the same folder as " I cant start my bike"...

Even notice that when you chop the throttle, the "vibs" go away?

Much of what your feeling is "power impulse", not all vibration.

Detune about 25 hp out of your bike, and it will all go away.

:roll:

Just different

Posted: March 27th, 2009, 7:28 pm
by exackery
I just got the AF last fall using the same motor I've been running since 2000 (original crank/bearings steahly weight (7oz)). The AF is a lot different than the steelie. Quite a bit less vibes at idle and quarter throttle-ish. When you do fast fireroading mostly 4th 5th gear stuff I think the AF vibrates more, Well, maybe not more but differently than the steelie --> i notice it. Could be more a case of used to the old feelings and not the new ones yet

Posted: March 28th, 2009, 8:19 am
by big_bore_500
Thanks for all the useful suggestions eg. quit being a pussy, harden the fuck up (my personal favorite lol) By the 2nd last race I decided to pull of the wheels and balance them. The rear wheel took 6 oz. :shock: and the front took 4 oz. What a difference! 85% better. was able to the 3 hrs. no problem. I should of thought of this sooner, with 500+ screws and the inner liner these wheels are close to 50 pounds a piece that is a massive amount of rotating weight at 80+ mph. Think i might even try this on the summer wheels. Although summer speeds tend to be quite a bit slower.