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]

[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 :brick: 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 :yes:

[MidnightMike]

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

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

[Crasherfromwayback]

[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 :brick: 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 :yes:
Mate, did that thing ever hold together for a whole lap?

[sugilite]

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]

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

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

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.

[White trash]

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.

Dunno if you mean me, but I still have wet dreams about that 5 minute ride on the RMZ on race slicks. Fuck me they're WICKED. The thing just never stops pulling (bit like me)

[sugilite]

lol, nothing 'fresh' about me mate.
OI! That post was for MidnightMike :bash:
When ya get to 1000 posts here, you become a official forum whore

So those tears as you parted with the 500 were just Crocodile ones eh, had me fooled, your acadamy material for sure :doobey: hehehe

I luv dat 500, it's got the knobblies on at the moment.
As soon as you can ride, come up to my rehabilitation clinic.
I'm surrounded by the largest farm in the southern HB and can ride it anywhere any time, and I have a 50 km gravel road loop where most times you do not even see a single vehicle. Did I mention it had a awesome 7km hill climb?
you know it's good for you, so let me know when ya ready....

[UrbanMyth]

woah, that intresting that the 4s are more to run then the 2s i dont know much about dirt bike riding and i wont pretend that i do lol.

[Wellyman]

Basically a two sroke can be easier to run , in the long run,but it costs alot when it all goes wrong. 4 strokes last a long time and are very expensive for a basic service, but in saying that I have been running my 230 for 2, nearly 3 years without a problem and haven't openened her up yet for valve check etc.
WM

[TwoSeven]

I disagree with some peoples theories on the cost difference between the bikes.

As far as I can see other than the engine, there is no difference between a 4-smoke and a 2-smoke (frame, chain, sprockets, tires etc) - so in that regards, the costs should be the same (assuming the usage is the same - which would be a given or you couldnt compare them).

Now, in the engine department a 2-smoke requires oil to be purchased as well as fuel, a 4-smoke doesnt. Rest of the oil in the engine should last about the same.

Plugs should be the same (given the same number of cylinders), and so should oil filters (and on dirt bikes I suspect both require air-filters changed just as often).

So - the only real difference is that a 2-smoke is going to require piston and rings where a 4-smoke usually doesnt. All other parts should wear just the same given the same usage.

Now, most of the bikes i've owned messed around with, are good for about 100k+ miles before the engine really needs anything doing to it. More often than not, mainly bearings and other loaded bits require replacing.

So, the question is - what is the cost of replacing piston and rings in a 2-smoke over 100k+ miles vs giving a 4-smoke a basic strip down at the 100k mark.

One cant compare racing or different usage models because that comes down to the level of tuning and required frequency of rebuilds. Trying to compare a bike thats built to run 500km on a race circuit to one thats built to run 1500 is going to be silly isnt it?

For those who are making general statements about bike type x costing more - I'd really like to see some numbers put up to prove those rather bold statements - I suspect they are probably comparing a $20k+ piece of the latest platic road bling with a $6k tank built for driving off cliffs.

edit: I like it when it displays the message "Posting quick reply - please wait" :)

[cheese]

Yeah but your 230 is more in lines with teh older style 4 stroke platform. the likes of teh CRF250 are is a higer performance platform, basically you are looking at teh same time for piston changes (if not it's only a 50 odd hour difference) and teh 4s bits are twice the price, twice teh moving parts. etc, etc.....

It's like compairing a high performance everyday car and a F1 car engine.

[Ixion]

Transmission oil in a two stroke only needs to be changed once in a blue moon, since it isn't contaminated by combustion by products. And you can use a proper transmission oil, since it isn't doing double duty. In my experience (and I've had a lot of 2 strokes and a lot of 4 strokes, though road bikes only) the oil costs works out pretty much the same, especially once you factor in that the two stroke has no oil filter to replace.

I think the biggest determinant of wear (and thus maintainance costs) is revs (assuming equal build quality and such like) . So it becomes hard to answer the question of what you are comparing with what. A 3000 rpm Harley with a RGV250 ? A 7000 rpm GT750 (they last forever) with a 19000 rpm ZXR250 ? And even if the peak revs are the same, how much is the rider going to want/need to rev it in actual use . GT750 has such low wear because in practice you seldom need to rev beyond 3000rpm.

Overall, wielding a very broad brush, I'd say that it is much of a muchness if you do your own work, and are thus just comparing parts costs. Differences are slight enough, compared with cost of fuel, tyres, chains etc etc that it's not worth differentiating.

I'd agree with the 100000 km figure, extra cost of one extra set of rings for the two stroke at 50000km is offset by the extra cost of camchain (and maybe valve springs , valves, guides) on the 4 stroke. If you're unlucky with the 4 stroke, it can be a fair bit more expensive . If we are talking the latest off road competition machines with titanium valves and goodness knows what other nonsense (what's wrong with good old cast iron, anyway), then the two stroke will be much much cheaper.

If you pay a dealer to do the work, 2 stroke will always come out well ahead, just beacuse if the labour saving. So quick and easy to do.

[MidnightMike]

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.

You mean when the four stroke needs a rebuild or for other things??? because i have an opportunity to buy an rg150 but ive been told that they drink oil like its the worlds greatest beer.

[sugilite]

Yes, I was just talking about motor rebuilds, as in 2 stroke vs 4 stroke.
As pointed out by others, the oil does really add to the day to day running costs, and 2 strokes are not known for being economical on gas.
Normally factories run those pumps pretty rich, but even leaning it out would not make a drastic difference to the cost of running it.

I guess you would need to check out the purchase price difference between the RG150 and 240 4 stroke 250 and see if it is worth doing?
I'd be suprised if a thread discussing such things has not already been started, so it may pay to try a search on the subject.

[Motu]

Going back to the original post I'd presume we are talking late model Enduro and MX bikes,and that means modern 4 stroke - my first reply was about new bikes...fuel,oil and a spark plug is all you'd use in each for moderate use in a year.But the thumper costs heaps more,for serious use they will change the synth oil every ride,that's more oil than the smoker will use....and for a mere mid season spruce up,the 2 stroke will just need rings and a powervalve clean,even a piston is cheap.But the 4 stroke will need possibly a chain valves and springs.Have you seen the pistons in these things? Like a Formula 1 piston,it's a wonder they don't flip over sideways in the bore.In no way are they anything like a good old XR250.

For a trail bike my DT230 makes as much HP as a 4 stroke twice it's size and half as heavy again,goes like a cut cat and hasn't been apart in nearly 30,000km - fuel,oil and a spark plug,change the gearbox oil,that's a years maintenance.

[TwoSeven]

I'd be interested in seeing the cost comparisons between say a single cylinder 4-smoke dirt bike and the equiv 2-smoke dirt bike.

[Sketchy_Racer]

I dunno about the oil factors.....

My KR used 700ml of two-S oil in 1000kms of riding.

$15 gas gets me 250kms. so around $60 for gas and $15 for a 1 litre oil.

1000kms = $75

now, my CBR 250 did 1000 kms and it cost $30 to every 300kms .

and oil needs to be changed every 10000kms with oil been $50

so $100 for a 1000kms petrol and $5 of oil costs.

$105 for a 1000kms on a 250 four stroke

$75 for a 1000kms on a 150 two stroke.

piston on the KR need to be done every 20000kms

at a cost of ~150 - 200 ??

with the extra money saved on the two stroke which is $600 over 20000kms
i can get a new piston kit for $200 and still have saved $400 by running the 150cc instead of the 250cc

Never worry about doing the pistons on a 250 4 cylinder, cause if it needs pistons its already fucked.

Same amount of riding, only a $400 difference after 20000kms.

Another factor to think about is the ease of the job.

Doing a piston change on a two stroke is a piece of piss and any joe blog can jsut about do one, heck even Ivan can do one and hes the dumbest red neck you'll ever see.

But Four strokes are harder and normally require a shop to do them, and take much longer and cost more for parts.

A Two stroke is cheaper in the long run any day of the week. But there are so many variables that it is impossible to judge them like that.


-RG

[cowpoos]

I've heard...dunno how true...that husberg 4st engines [larger ones 400cc+]are lower reving and there fore more reliable and cheaper to maintain than comparable bikes? has anyone heard this or know anything about them?
as I've been toying with the supermotard Idea....but it has to beable to do offroad dutie as well....and big KM's....as it will be used on farm duty aswell [I can see the heads nodding back and forth about the farm dutie coment...I use a klx300 as a toy/farm bike at the moment and its brillent....but I wan more and I want it to be easily road legal]

[Wellyman]

Dunno if you mean me, but I still have wet dreams about that 5 minute ride on the RMZ on race slicks. Fuck me they're WICKED. The thing just never stops pulling (bit like me)


The more posts of yours I read of yours the more sorry I feel for Riff Raff!:laugh:
WM

[Bangbug]

Why not have the best of both worlds?
Supercharge a 2stroke?
Forget running oil in your fuel (why make diesel?)
Don't know why we haven't seen one yet (apart from i guess it'd be a bit bigger n all) Maybe they are looking to recruit test pilots? Oooh oooh pick me!
:scooter:
I've only ridden one 2 stroke.............. lordy they are marvellous. Suck a bit more gas though, the older ones are a bugger to find parts for though :(
New ones i have no idea, id love to have a zap on a new 250 2stroker...... just so i can feel the pain again :P
Now where did i put my pills????????

[TwoSeven]

$105 for a 1000kms on a 250 four stroke
$75 for a 1000kms on a 150 two stroke.


A 250cc machine is effectively 66% bigger than the 150, so I think that would would have to make them comparable

In effect the 250 remains at $105, but to make the 150 equiv. I think one would have to make it like a 250, so $75 * 66% = $125. In that respect it is actually more expensive to run the 150 over the 250 in hyperthetical terms.

However, in reality the smaller the capacity the cheaper the cost of running - so one cant complain - even the tire cost would make up a heck of a lot of difference :)

I'm getting between 17 and 19 km/litre out of my Krappi 400, so for my $10 I get roughly 100 or so kms out of it. That kind of works out at about the same as the old cibby. Difference is that the krappi is an air cooled parallel twin and spends most of its time at 50km/hr. It would explode if I tried to drive it like the ol cibby.

[Crasherfromwayback]

Dunno if you mean me, but I still have wet dreams about that 5 minute ride on the RMZ on race slicks. Fuck me they're WICKED. The thing just never stops pulling (bit like me)

If I'd mentioned wet dreams for sure I would've been referring to you.
I was referring to old Sugilite (who I sold my last KX500 to).
We raced eachother at that motard meet in Upper Hutt (you were there you goober) and got a chance to line them up side by side.
Until he repeatedly carried out facial track inspections that is.
I'm with you at the mo though mate....all I can do with my 450 now is wash it down with man custard....sure as fuck not able to ride it just yet!
I'll be back.
Might just have to get someone to start it for me.....

[Wellyman]

They are a alright the RM-Z's but I hate the blue seat covers they ae putting on them what the hell is with that!!!
WM

[Crasherfromwayback]

You're so right mate, I hate that myself!
Luckily mines an '05' with the black/yellow cover!

[Wellyman]

You're so right mate, I hate that myself!
Luckily mines an '05' with the black/yellow cover!

They look so much fucken nicer then the blue seat poofy shit!My boss has a DRZ 2fiddy with yellow seat, and I was comparing it the other day and his older model looks so much nicer.
WM

[Sketchy_Racer]

A 250cc machine is effectively 66% bigger than the 150, so I think that would would have to make them comparable

In effect the 250 remains at $105, but to make the 150 equiv. I think one would have to make it like a 250, so $75 * 66% = $125. In that respect it is actually more expensive to run the 150 over the 250 in hyperthetical terms.

However, in reality the smaller the capacity the cheaper the cost of running - so one cant complain - even the tire cost would make up a heck of a lot of difference :)

I'm getting between 17 and 19 km/litre out of my Krappi 400, so for my $10 I get roughly 100 or so kms out of it. That kind of works out at about the same as the old cibby. Difference is that the krappi is an air cooled parallel twin and spends most of its time at 50km/hr. It would explode if I tried to drive it like the ol cibby.

Yes, but if you were to compare a two stroke bike with a four stroke,

its normally about double the cc for a 4 stroke .eg

150 2T = 250 4T

250 2T = 500 4T

and so on.....

plus, i would have my KR anyday of the week over the cbr.

To many things going round and round in a CBR for me. One piston works effectively. ;)

[crazyxr250rider]

Going back to the original post I'd presume we are talking late model Enduro and MX bikes,and that means modern 4 stroke - my first reply was about new bikes...fuel,oil and a spark plug is all you'd use in each for moderate use in a year.But the thumper costs heaps more,for serious use they will change the synth oil every ride,that's more oil than the smoker will use....and for a mere mid season spruce up,the 2 stroke will just need rings and a powervalve clean,even a piston is cheap.But the 4 stroke will need possibly a chain valves and springs.Have you seen the pistons in these things? Like a Formula 1 piston,it's a wonder they don't flip over sideways in the bore.In no way are they anything like a good old XR250.

For a trail bike my DT230 makes as much HP as a 4 stroke twice it's size and half as heavy again,goes like a cut cat and hasn't been apart in nearly 30,000km - fuel,oil and a spark plug,change the gearbox oil,that's a years maintenance.
Some have teflon skirted pistons....

[Ixion]

Meh. What's wrong with cast iron, I say.

[IronicCapers]

Two simple things to remember

2stroke=dead simple engine, easy and cheap parts to manufactuer. Only downside if your a greeny is bad enviromental impact.

4stroke=Advanced engine, dam pain in the arse to get power out of. Valves annoying. Heavyr.

4-2= 2 reasons not to get a 4stroke

Joe Bloggs is a dumbarse but a good friend of mine (not to be confused with me) But he gives his thumbs up on maintenance and expenses
:first:

[TwoSeven]

Exactly what is advanced in a 4-smoke engine. Pistons, rods, valves, crank, cam, gears. Cant get more simple than that. Piston goes up and down, some things turn around.

[Sketchy_Racer]

Cam timing advances.... Variable valve timing on the Bandit 250s....

Tcss = Twin chamber swirl system on suzukis or some bull shit....

but hey just get a 2 stroke and all you have is a piston going up and down :done:

[IronicCapers]

The pain in the anus timing, the addtional hoopla or the valve not to mention the cost of them(precision machined) And is it titanium intake and stainless exhuast? Not cheap materials. all the additional fiddly fucks and chucks that are required for the 4-smoker. And then theres the thing that happens when an average not that knowledgable about bikes person takes off the head."Fuck this SHit" Valves clearances for 1(not hard for me or maybe you but how many people will no of the lil tools that make it easier. Take off the head of a 2stroke and all you see is the piston dead simple. Point proved. Happy.


I am:doobey:

[yokel]

and (mx) 4strokes are harder on the runin gear (chain, gear box and stuff) coz they take 4strokes to do full power cycle in sted of 2 or so im told make sense to me

[Crasherfromwayback]

That bits not quite right....

[Sketchy_Racer]

he is right about the 4T being more harsh on the runnning gear

a 4T has to wait 3 strokes before it gets one big HIT which slams through the running gear.

If you ride a older big thumping 4T and use very very low revs you can feel the thumps from the engine firing. As the revs gain, the thump becomes more of a vibration, but it is still doing the same to the drive gear.

A 2T fire every 2nd stroke.... im sure you get the rest.......

[SLight]

Amittedly 4 strokes are getting up there these days power wise. But due to the lightened engine internals, things do not last as long as they did. The valves tend to stretch very easily and cost a fortune to service every xx hours. I know a dude, ex pro racer that has owned a 92 KX500 from new and has only late last year had to pull her down for inspection only. He shouted it a birthday while he was in there. Thats a pretty good run? Its had a lot of work. These bikes are torque monsters. But still have the top end rush. I've yet to see any 4 stroke get past me. Mines only lightly moded with FMF pipe V-Force2 reed block and mild porting. Reguarding oil for it, she runs on Ams100:1 which works out heaps cheaper cause you use half the amount of the other leading brand recommendations. (good ones 50:1) Mind you if you road racing you run a little richer to compensate for more W O T. In my mind 2 strokes, especially powervalved models, are gonna take a lot of beating.


LONG LIVE 2 STROKES.:first: