[jkb4c]

Hey guys. I'm doing a little research on motorcycle engines - more specifically, the longevity of these engines under various uses.

If you've ever blown an engine, in an SV or otherwise, please chime in with your experiences. Thanks in advance!



Bike year/make/model:

Approximate mileage when the engine grenaded:

Do you know what happened to the engine? (I.E. spun bearing, etc):

Did you do regular maintenance, oil changes, etc?

How many miles do you, personally, expect out of a motorcycle engine?

 

[Guest]

1981 Yamaha RD350LC

Cruising along at 75 mph in spring 1995, the rear tire locked up without warning, leaving a 100-foot black mark by the time I pulled the clutch in.

The engine had seized solid. When I took it apart, I was lucky: only required a top-end rebuild. The cylinder walls for both cylinders looked "burned." The damage was worse in one cylnder: pieces of the rings were sitting on top of one piston and also lodged in the exhaust port.

Somehow a horse fly managed to get into the injector oil reservoir tank and then into the hose that leads from the tank to the pump, clogging the oil supply line and starving the pump that feeds oil to the carbs.

Fixed with a new piston kit, cylinder honing, head planing, and a gasket set. When I got it all back together, I subsequently disconnected the oil injector and thereafter always mixed my own fuel/oil. I rode it that way (virtually trouble-free) for another 8 years or so.

 

[arthursc2]

1994 Yamaha Seca Div II
28,xxx miles
Spun the 3rd rod bearing. Those bikes dont have a rev limiter, and I over revved it, with not enough oil, and see ya. Bearing toast.

That was my first bike. Learned alot. My SV has 36k on it. Taken care of religiously. I change the oil when it gets dark, so sometimes an oil change only lasts a track day. Coolant was flushed twice this year. Once because I pulled the rad ro fix a pin hole, and the other time because I lost coolant pulling the clutch cover off.

I imagine I will hit 60k at this rate before I have a distinct failure of any kind.

 

[jolt]

Very close to losing a bearing. Installed new clutch, with new housing but totally forgot to install old oil pump gear....oops!! went to adjust the clutch, didn't have cluster installed so no oil light, ran for about 5-10 mins before i realized. I got lucky, very lucky.

 

[dmmcd]

Well, it wasn't on a bike exactly...

It was a GSXR engine, late 1990s vintage that was installed on a custom built race car (Formula SAE). Mileage unknown. Well maintained, though.

We were doing autocross events, and during one lap one of the pistons seized and blew a giant hole in the side of the cylinder, spraying parts and oil all over the track. Everyone was angry because it took a good hour to clean up the mess.

Motorcycle engines aren't designed to take lateral loads, and we think the oil all sloshed to one side during a sweeping turn, thus starving the cylinder and leading to the seizure.

I expect (under normal use and proper maintenance) a motorcycle engine to last 100k miles, at least.

 

[amcquinn86]

1st time:

Bike year/make/model: 2001 Kawasaki Ninja 250

Approximate mileage when the engine grenaded: 16,000

Do you know what happened to the engine? (I.E. spun bearing, etc): Too lean, wrong plug. Burnt hole in piston.

Did you do regular maintenance, oil changes, etc? Oil change & valve adjustment were done. As a newbie I didn't know any better and didn't check the PO's jetting and plugs, both of which were way wrong.


--------------------------------
Second time:
Bike year/make/model:2002 SV650s

Approximate mileage when the engine grenaded: 16,000

Do you know what happened to the engine? (I.E. spun bearing, etc): Oil pump failure led to melted main bearings.

Did you do regular maintenance, oil changes, etc? All regular maintenance done.

Oddly, both times were on the same road, within a mile of each other 185 miles from home.

 

[jameswing]

Oddly, both times were on the same road, within a mile of each other 185 miles from home.

You need to stay off that road when you're anywhere near 16K Mi. And where is this road so I can stay clear as well?

 

[Gerard7aa]

I've only blown my first dirt bike's engine....
How was I supposed to know you mix the oil in the gas....!

 

[svscott]

1984 Kawasaki KZ440 - riding home from work and started knocking, ALOT - I heard some bearings went, I gave the bike away and bought the SV new in 03 and have abused it plenty without any issue since then!

 

[Chilltake]

Bike year/make/model:
2006 SV650S


Approximate mileage when the engine grenaded:
12,000


Do you know what happened to the engine? (I.E. spun bearing, etc):
Rear piston seized in the cylinder. Exact cause unknown. Had it fixed under warranty. I was doing around 110mph on the autobahn when I lost 90% of the engines power. I still made it home, dealer had it fixed within about 2 weeks. Really sucked.


Did you do regular maintenance, oil changes, etc?
Dealer kept at the time


How many miles do you, personally, expect out of a motorcycle engine?
100k or so

 

[svfox]

Bike year/make/model:
2002 SV650S


Approximate mileage when the engine grenaded:
30,000 km

Do you know what happened to the engine? (I.E. spun bearing, etc):
Rear cylinder big end bearing went caput, scored crank etc....

Did you do regular maintenance, oil changes, etc?
Yes, bought used at around 26,000 km though, may have been run on low oil at some point? still unknown

How many miles do you, personally, expect out of a motorcycle engine?
100k or so

 

[jkb4c]

Thanks for all the responses. I'm compiling all these into a file on my computer for use in a project I'm working on for school.

I wonder what caused the oil pump failure/rear pistion seizure mentioned in the two earlier posts? Isolated incidents? Hopefully so.

Keep 'em coming!

 

[Chilltake]

I personally have the feeling my rear cylinder got overheated somehow. I didn't have a chance to see the damage (because the dealer fixed it). I just know that everything between the head and bottom end of the rear cylinder (including the cylinder itself) was replaced by the dealer.

The dealer mentioned that he had NEVER seen this kind of damage to an SV motor. It was at least not due to bad maintenance or so. Ah well, guess I'll never know


EDIT: fixed typo's

 

[JollyGQ]

Hmmm...well, I haven't had my engine blow yet, but now y'all got me worried...lol. I go through about a pint and a half of oil every 500 miles or so dpending on how I ride...but it's pretty regular. Most of the time, I remember to catch it before the oil is no longer showing in the window. I've got almost 50k on my 04 now...thanks for scaring me...lol

 

[jkb4c]

Hmm. A pint and a half every 500 mi seems like a lot to me. It's burning off - not leaking, right?

Other than that I wouldn't be too worried - it seems like other than the odd occurrance, the SV engine can make it to 100,000 miles easily with regular oil changes and maintenance. Then you can just overhaul it and keep on going!

 

[jdewkilla]

ummm.. yes

 

[nokturnal]

i have blown an engine. the details are too painful to discuss.

 

[Veee]

Hmm. A pint and a half every 500 mi seems like a lot to me. It's burning off - not leaking, right?

Other than that I wouldn't be too worried - it seems like other than the odd occurrance, the SV engine can make it to 100,000 miles easily with regular oil changes and maintenance. Then you can just overhaul it and keep on going!

I bet there is more blown motors than those that made 100k. ;D

 

[jkb4c]

I would agree with you, but I'd also like to see how many of those blown engines got regular oil changes and were never starved of oil. The SV engine seems pretty robust.

 

[Veee]

I would agree with you, but I'd also like to see how many of those blown engines got regular oil changes and were never starved of oil. The SV engine seems pretty robust.

oil starvation may not have anything to do with oil level or frequency of oil change. some did due to wheelies, some did anyway, first gen.
there is also good number of well maintained bikes breaking crank.
and there is huge number of them blowing up on track that see more maintenance than any street bike.
personally I have blown more of them than I even heard of having 100k. ;D