Just trying to get some general info, what would you experts says breaks down the most, generally, on motorcycles?

Are you talking the bike in general? Or a specific area?
In general I'd say carbs are the most troublesome part. Followed by the chain/sprocket most bikes have. Then I'd have to say the clutch after that.

And I know chain/sprockets are designed to wear out, but most are misadjusted and so wear out/break more often than they should.

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Have owned - 2001 Suzuki Volusia
Current bike - 2005 Kawasaki Z750S
MMI Graduation date January 9th, 2009. Factory Certifications in Suzuki and Yamaha

Good sense and speed limits, in that order.....


.... and pretty much much what wrider said, too...


..... oh yeah, and tires.... you can chew through those in a hurry... not really 'breaking' either.... but still a rather involved mechanical operation to change...

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No Witnesses....

You have a good question. General or specific. I was kinda going after, I don't know if I can do this, the 80/20 rule. What 20% of the parts, generally cause 80% of the problems in terms of breakdown. I.E, do certain electrical parts break a lot, is it lights, or fuses, or chains or sprockets like you say.

I'm looking at inventorying some parts and wanted to look at some things generally to stock.

Thanks for your help

Depends on the bike. Most modern bikes are very reliable if they have not been abused. I can't think of anything off hand that would be necessary to have a stock of.

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'07 Suzuki V-Strom DL650
An armed man is a citizen, an unarmed man is a subject.
Molon Labe!!!

This runs the gamut. In my opinion, as other posters have said, a properly maintained and cared for modern motorcycle is quite reliable.

From my experience, I tend to have more electrical problems than anything else. And I've owned a mix of Japanese and Italian bikes. I've had 4 voltage regulators go out. 3 on a Suzuki and 1 on a Ducati. I've had a fuel filter rupture (odd ball low probability event... but it happened).

Knock on wood but in 14 years and a 100K of commuting and traveling by bike, I haven't been stranded due to a mechanical. Not even so much as a flat tire.

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Two Big Jugs or Four Small Cups. Life's Good.
`08 CBR1000RR "Ayane" - the Shinkansen
`07 S4Rs "Persephone" - urban Monster
`00 SV650 "Ayame" - trackday special

As far as things to stock I'd say an extra chain and sprocket. Followed by brake fluid/oil. Then that's about it. Maybe if you're really paranoid some extra carb needles/jets and clutch plates, but I wouldn't worry about those.

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Have owned - 2001 Suzuki Volusia
Current bike - 2005 Kawasaki Z750S
MMI Graduation date January 9th, 2009. Factory Certifications in Suzuki and Yamaha