2 stoke vs 4 stroke maintenance cost

[khabel]

Over a yearly period and with no major problems whats the difference in maintenace costs between a 2 stroke and 4 stroke if both bikes were only a couple years old?

[Motu]

Oil,fuel and a spark plug? If more than a couple of years old or if these bikes get some very serious use in those 2 years,I'd say the 4 stroke was going to cost more.

[Crasherfromwayback]

Oil,fuel and a spark plug? If more than a couple of years old or if these bikes get some very serious use in those 2 years,I'd say the 4 stroke was going to cost more.

So true Dude...
I was a die hard two stroke fan, but the latest generation four strokes are so good, I found myself on one.
BUT, they are considerably dearer to PROPERLY maintain.

[khabel]

So true Dude...
I was a die hard two stroke fan, but the latest generation four strokes are so good, I found myself on one.
BUT, they are considerably dearer to PROPERLY maintain.

Care to explain a bit more?

[Crasherfromwayback]

I ran KX500's for years, moto-x, road raced them, and beach raced them.
That's hard on a big (or any) two stroke.
But even if you slip a new piston and ring set into them often, it costs sweet fuck all compared to doing likewise on a modern four stroke.
And the way the new generation four strokes rev, the eat up engine internals ever bit as quick as a two stroke, but there are MORE bits to replace.
I rebuilt my 450 before Wanganui, and to do so needed valve springs (x4), they're such light steel as the titanium valves weigh nothing, but they don't last. If you don't do them, they loose tension and the piston and valves will meet at high revs. Not nice. Then you need head and base gskts (dearer than most two stroke bits anyway), where as most two strokes you can leave the cyl head on and just use a new base gst. The piston and ring assemblies are dearer (oil control rings as well, where most modern two strokes only have the one ring)....the list goes on....not to mention the time involved. Having said that.....my 450 is as fast as my old KX500 (fact, another member here will vouch for that!), but heaps nicer and easier to ride.
So, while I think it's worth it, you've gotta choose carefully.
If I didn't work in a Suzuki Dealership, I'd have to think REAL hard, because even though my bits cost me a lot less than a retail paying cutomer, it's still REAL dear.

[clint640]

Good comments above re the new high revving MX 4 strokes, but it does depend on the bikes you are comparing, if you're looking at getting a basic trailbike then (for example) a well maintained XR 250 could be a bit cheaper to maintain engine wise than a equally well looked after KDX 200 of the same age.

Cheers
Clint

[Crasherfromwayback]

Good comments above re the new high revving MX 4 strokes, but it does depend on the bikes you are comparing, if you're looking at getting a basic trailbike then (for example) a well maintained XR 250 could be a bit cheaper to maintain engine wise than a equally well looked after KDX 200 of the same age.

Cheers
Clint

Yeah good point, I should've asked.
Still plenty of XR500A's running round probably still on original pistons!
I was referring to modern MX bikes.

[cheese]

I've heard that alot of people are going back to two strokes. Pissed off with high bills for there modern 4's.

Put it this way, I got an engine rebuild kit form ebay for my RM, $250 nzd for piston, rings, conrod, all gaskets, seals, etc. Get that for a 4!!

Plus it's nice to not feel like you are attached to a tree by a massive bungy ever time you let the throttle go.

[sugilite:Me]

[QUOTE]=CrasherfromwaybackHaving said that.....my 450 is as fast as my old KX500 (fact, another member here will vouch for that!), but heaps nicer and easier to ride.
/[QUOTE]
Hmm, as I remember I was inspecting the road surface very closely that day a couple of times but yes I did look up long enough to realize that on that track your 450 was definitly a notch up on the 500, as was your riding lol

My time on manfield with shitty cast iron cylynder fitted was a flat 1:18 (standard nikosil barrel was much faster RIP) and I'd be suprised if a 450 4 stroke could match that, but I do stand to be corrected

[MidnightMike]

Is it the othe way around for road bikes or not?
eg. RG150 vs ZXR250

( I had to do the size thing cos no one would answer me. )

[Crasherfromwayback]

[QUOTE=sugilite][QUOTE]=CrasherfromwaybackHaving said that.....my 450 is as fast as my old KX500 (fact, another member here will vouch for that!), but heaps nicer and easier to ride.
/

Hmm, as I remember I was inspecting the road surface very closely that day a couple of times but yes I did look up long enough to realize that on that track your 450 was definitly a notch up on the 500, as was your riding lol

My time on manfield with shitty cast iron cylynder fitted was a flat 1:18 (standard nikosil barrel was much faster RIP) and I'd be suprised if a 450 4 stroke could match that, but I do stand to be corrected

Mate, did that thing ever hold together for a whole lap?

[sugilite:Me]

Yeah it did, several in fact lol
The secret to getting it to survive circuit racing as I now know is standard nicasil barrel AND standard piston with high octane gas. take one of those items out the equation and it goes bang.
I can resurrect the barrel, but need 1K to do that and the rest of the job properly, hence I'm not racing it till that is done cuz the steel liner SUX
Unfortunately I had put a wisco in, drilled it for more oil flow, warmed it up real careful, then seized it, plenty told me after woulds, ahhhh seizco pistons have that reputation, fuck it.

[Crasherfromwayback]

Such problem with my 450 Tall Boy!

[sugilite:Me]

Is it the othe way around for road bikes or not?
eg. RG150 vs ZXR250

( I had to do the size thing cos no one would answer me. )

OK you fresh whore you! I'll "attempt" an answer on this.

Rule of thumb is equal capacity, the 2 stroke will make more power than a 4 stroke.
HOWEVER- 2 stroke technology is stagnant in the motorcycle industry, they just do not develop them anymore due to pollution etc (personally I mourn the 2 strokes and have no doubt they would still kick 4 stroke arse had they kept developing them, esp roadbikes) There was this Australian developed orbital technology that surfaced once in a while, it directly injected into the heads, with MUCH lower emissions, it was developed for outboard motors for boats. For some reason, it was never taken up for bikes. so these days, 4 stokes of equal capacity have pretty much caught up on the power stakes. I'd imagine the performance of the 2 bikes you list would be similer with the ZXR having a higher top speed.

As for maintenance between a RG150, and ZXR250, I'm guessing that with 4 pistons and a lot more complexity the ZXR would be a lot more expensive to maintain over a extended period.

[Crasherfromwayback]

OK you fresh whore you! I'll "attempt" an answer on this.

Rule of thumb is equal capacity, the 2 stroke will make more power than a 4 stroke.
HOWEVER- 2 stroke technology is stagnant in the motorcycle industry, they just do not develop them anymore due to pollution etc (personally I mourn the 2 strokes and have no doubt they would still kick 4 stroke arse had they kept developing them, esp roadbikes) There was this Australian developed orbital technology that surfaced once in a while, it directly injected into the heads, with MUCH lower emissions, it was developed for outboard motors for boats. For some reason, it was never taken up for bikes. so these days, 4 stokes of equal capacity have pretty much caught up on the power stakes. I'd imagine the performance of the 2 bikes you list would be similer with the ZXR having a higher top speed.

As for maintenance between a RG150, and ZXR250, I'm guessing that with 4 pistons and a lot more complexity the ZXR would be a lot more expensive to maintain over a extended period.

lol, nothing 'fresh' about me mate.
Please don't forget Old Bean...HP and torque can also be attained with an increase in revs. KX 500's top out at 7500, RMZ450 9750. Rev your KX500 to that and see what happens. I tried.