very strange cadence of vibes at 75mph on the KLR

go::ahead · 11-30-2012, 03:23 PM

So its no surprise the pig is vibey at super slab speed, however in the 6 months of having the bike I've gotten used to it although I try to stay below 75. The bike has been running like a top since getting through the long list of maintenance that was overdue but this morning I had to take the interstate (speed limit 75) to a meeting and discovered an extremely strange yet consistant chatter from the bike.

At 73mph, just below 5k rmp, the bike would chatter as if going over a handful of bumps in the road. This would take 1 second, then bike would recover and hum along exactly 3 seconds, then more chatter for 1 second, repeat like a metronome.

Speeding up to 75mph (5k), then 77mph (just over 5k) the cadence would increase tempo but essentially be the same.

Cruising at 72 or less the bike hummed along just like always, buzzy but status quo.

This is a new one on me, sound familiar to anyone? I haven't done any engine work since the valves 2k miles ago, just regular maintenance stuff. This seems to have come from no where but the problem was exactly the same to and from work today.

tHEtREV · 11-30-2012, 03:57 PM

You're wheels are out of balance.

go::ahead · 11-30-2012, 06:19 PM

Quote:

Originally Posted by tHEtREV

You're wheels are out of balance.

You sure about that? I guess I should look closer but I don't think I threw a weight. If my wheels we suddenly out of balance the would wobble at all speeds with a constant vibe, not this weird stutter I feel every 3 seconds. Feels like the engine isn't getting fuel then suddenly catches a second later

lobolator · 11-30-2012, 07:05 PM

I use rim locks front and back. I only balance the front. At certain highway speeds I get a rhythmic rumbly vibe, like you describe. It's the rear tire.
My bike is a 250 DS so I don't worry about it. Not really going that fast ever.
If you want the best mileage from your tires or a smooth ride then you might want to balance the wheels again.

tHEtREV · 11-30-2012, 07:10 PM

Quote:

Originally Posted by go::ahead

You sure about that? I guess I should look closer but I don't think I threw a weight. If my wheels we suddenly out of balance the would wobble at all speeds with a constant vibe, not this weird stutter I feel every 3 seconds. Feels like the engine isn't getting fuel then suddenly catches a second later

No, I'm not sure.

It was the first thing that sprang to mind.

But having said that, 3 secs seems a long time in between shudders...

Is it speed related or RPM related?

If you sit on the same revs in 4th, is it still there?

If it is speed and not RPM I would lean toward wheels.

go::ahead · 11-30-2012, 10:01 PM

Quote:

Originally Posted by tHEtREV

No, I'm not sure.

It was the first thing that sprang to mind.

But having said that, 3 secs seems a long time in between shudders...

Is it speed related of RPM related?

If you sit on the same revs in 4th, is it still there?

If it is speed and not RPM I would lean toward wheels.

Good point on speed vs rpms, I guess I'll test that theory tomorrow. Much appreciated

Unstable Rider · 12-01-2012, 03:10 AM

Did you consider, loose, missing or BROKEN (sheared off) sub frame bolts?

The KLR famous for "eating" it's own subframe bolts.....

the factory ones are made from GLASS and GUMWRAPPERS.

Sometimes difficult to see or detect, cause the head side of the bolt may still be stuck in the hole.... look on the nut side, put a wrench on it or socket.... does the head turn on the other side? If not, it sheared within. I know, that all just sounds dirty, right?

Eagle Mike has a subframe bolt replacement kit.

I have also seen where engine guard bolts loosened up, which in turn radiated a harmonic vibe somewhat like you are talking of.

Beyond that, I would say get a forkbrace, lower the fender, and get a SuperMoto fender to reduce the wind knocking you around.

Just some ravings of a complete mad man. Did you say what tires you are running, how many miles are on em and stuff? Tire pressures?

What overall condition is the bike in? Miles?

Wondering if you could have a frame that is sprung or bent from a crash or go down?

They are pretty tough overall. I have a 2009 with no issues.

I do like the first gen. as well.

johnno950 · 12-01-2012, 03:25 AM

Have you blown a seal on the rear shock?,can cause rear wheel to skip/chatter.

Pantah · 12-01-2012, 05:48 AM

Sounds to me like your chain and sprockets might be the cause. What do they look like and is it properly adjusted?

Foot dragger · 12-01-2012, 05:02 PM

Quote:

Originally Posted by tHEtREV

You're wheels are out of balance.

Or the tires have the sort of knobs that dont like going down the freeway,at least that kind of freeway. Different surfaces can cause weird harmonics with tires.
Or the wheels are out of balance. Or the chain has tight/loose spots.

DirtDabber · 12-01-2012, 06:29 PM

Quote:

Originally Posted by Foot dragger

Or the wheels are out of balance. Or the chain has tight/loose spots.

Or both, that would explain the 3 seconds... It would take several rotations of the tire for the chain cadence to mesh with the tire cadence... Frequency would increase with speed.

go::ahead · 12-02-2012, 07:45 PM

So this is just after a short test ride but the vibes have vanished up to 80, this pig doesn't go beyond that!

I had been running TKC80's that had reached the end of their life and finally took the time to spoon on my new Kenda K761 rubbers. Either the tires, the chain tension, or as one of you suggested it was a combination.

As for the subframe bolts, the previous owner already took care of that but I do need to check them. I'm looking for a rent house with a garage right now, if that happens soon I'll tear down the KLR for a full rebuild this winter. After 40k+ miles this bike needs a healthy dose of locktite

go::ahead · 12-02-2012, 07:47 PM

Quote:

Originally Posted by johnno950

Have you blown a seal on the rear shock?,can cause rear wheel to skip/chatter.

I do know the suspension needs a rebuild for sure but that wasn't the cause of my superslab stutter

go::ahead · 12-03-2012, 01:34 PM

Quote:

Originally Posted by go::ahead

I do know the suspension needs a rebuild for sure but that wasn't the cause of my superslab stutter

Now I've discovered I'm getting the speed wobbles for the first time

I swear, this bike hates speed

elsalvadorklr · 12-03-2012, 04:15 PM

Quote:

Originally Posted by go::ahead

now i've discovered i'm getting the speed wobbles for the first time

i swear, this bike hates speed

adjust stem bearings

11-30-2012, 03:23 PM	#1
go::ahead ^OP Adventurer Joined: Jul 2012 Location: Santa Fe, NM Oddometer: 70	very strange cadence of vibes at 75mph on the KLR So its no surprise the pig is vibey at super slab speed, however in the 6 months of having the bike I've gotten used to it although I try to stay below 75. The bike has been running like a top since getting through the long list of maintenance that was overdue but this morning I had to take the interstate (speed limit 75) to a meeting and discovered an extremely strange yet consistant chatter from the bike. At 73mph, just below 5k rmp, the bike would chatter as if going over a handful of bumps in the road. This would take 1 second, then bike would recover and hum along exactly 3 seconds, then more chatter for 1 second, repeat like a metronome. Speeding up to 75mph (5k), then 77mph (just over 5k) the cadence would increase tempo but essentially be the same. Cruising at 72 or less the bike hummed along just like always, buzzy but status quo. This is a new one on me, sound familiar to anyone? I haven't done any engine work since the valves 2k miles ago, just regular maintenance stuff. This seems to have come from no where but the problem was exactly the same to and from work today. __________________ 2000 KLR 650 2009 Surly Karate Monkey, rigid SS 2012 Specialized Camber 29 2012 Masi CX SS

11-30-2012, 03:57 PM	#2
tHEtREV tEAM iDIOT Joined: Apr 2007 Location: Middle Park, Brisbane, Australia Oddometer: 5,516	You're wheels are out of balance. __________________ tEAM iDIOT... tHE oRIGINAL. Hard Core Dirt Touring.

11-30-2012, 07:05 PM	#4
lobolator Adventurer Joined: Jan 2010 Location: Corner of Kanc and Bear Notch Oddometer: 54	+1 on out of balance I use rim locks front and back. I only balance the front. At certain highway speeds I get a rhythmic rumbly vibe, like you describe. It's the rear tire. My bike is a 250 DS so I don't worry about it. Not really going that fast ever. If you want the best mileage from your tires or a smooth ride then you might want to balance the wheels again. lobolator screwed with this post 11-30-2012 at 07:11 PM Reason: clarification

12-01-2012, 03:10 AM	#7
Unstable Rider World Wide Inmate Joined: Jul 2010 Location: 10,000 Lakes Oddometer: 2,122	Did you consider, loose, missing or BROKEN (sheared off) sub frame bolts? The KLR famous for "eating" it's own subframe bolts..... the factory ones are made from GLASS and GUMWRAPPERS. Sometimes difficult to see or detect, cause the head side of the bolt may still be stuck in the hole.... look on the nut side, put a wrench on it or socket.... does the head turn on the other side? If not, it sheared within. I know, that all just sounds dirty, right? Eagle Mike has a subframe bolt replacement kit. I have also seen where engine guard bolts loosened up, which in turn radiated a harmonic vibe somewhat like you are talking of. Beyond that, I would say get a forkbrace, lower the fender, and get a SuperMoto fender to reduce the wind knocking you around. Just some ravings of a complete mad man. Did you say what tires you are running, how many miles are on em and stuff? Tire pressures? What overall condition is the bike in? Miles? Wondering if you could have a frame that is sprung or bent from a crash or go down? They are pretty tough overall. I have a 2009 with no issues. I do like the first gen. as well. __________________ ´¯`·.¸¸.·´¯`·.¸ ><((((((º> `·.¸¸.·´¯`·.¸¸.·´¯`·.¸ ><((((º> ´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸ ><((((((º> Everything happens for a reason. "Still seeking the reason"

12-01-2012, 05:48 AM	#9
Pantah Red Sox Nation Joined: Oct 2004 Location: India Wharf Oddometer: 8,901	Sounds to me like your chain and sprockets might be the cause. What do they look like and is it properly adjusted? __________________ Straight ahead and faster -Bo Weaver 1970 "There I was..." -Griffin Niner Three Hotel

12-01-2012, 03:25 AM	#8
johnno950 Gnarly Adventurer Joined: Jul 2010 Oddometer: 454	Have you blown a seal on the rear shock?,can cause rear wheel to skip/chatter.

12-02-2012, 07:45 PM	#12
go::ahead ^OP Adventurer Joined: Jul 2012 Location: Santa Fe, NM Oddometer: 70	So this is just after a short test ride but the vibes have vanished up to 80, this pig doesn't go beyond that! I had been running TKC80's that had reached the end of their life and finally took the time to spoon on my new Kenda K761 rubbers. Either the tires, the chain tension, or as one of you suggested it was a combination. As for the subframe bolts, the previous owner already took care of that but I do need to check them. I'm looking for a rent house with a garage right now, if that happens soon I'll tear down the KLR for a full rebuild this winter. After 40k+ miles this bike needs a healthy dose of locktite __________________ 2000 KLR 650 2009 Surly Karate Monkey, rigid SS 2012 Specialized Camber 29 2012 Masi CX SS

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