Tune Up Costs - n00b Question

[Black]

Hello Everybody,

I've come to the conclusion that I think my bike needs some professional help.
It doesn't seem to run smoothly even at higher revs and when I first start her up (before its warmed up or after its been resting for a while) I have to fight to keep her running until I'm moving.
Sometimes when I'm at an intersection it stalls when idling (which is a pain in the @rse when its kickstart only)
Here is what happens:
I start it up and it idles ok.
Try to give it ANY throttle and buurrrr ... it dies.
If I can start it up and keep the revs above 4k its ok, as soon as I let them fall below 4k and buurrrr.
(NOTE: I have to have the choke out when this is happening or it wont start at all)

Once its been running for a while (Have to be riding, not idling) it doesn't die on me anymore.

Ok, to the questions:
Does anyone have any ideas as to whats wrong with my poor girl?
How much does a service & tune-up usually cost?

Thanks for any help you can give me.

Kevin

[EDIT]: Forgot to mention - my bike is an 88 TZR250 2-Stroke.

[Cibby]

well there's ya problem.

Its a 2 stroke.

I decline to comment further.

[SimJen]

helpful comment, but it will still beat your 4 stroke 250
Two strokes need to be well kept to keep em running right.
Sounds like it could be your carbs. Have they ever been cleaned? or rejetted wrongly by someone?

[Black]

Hi SimJen,

I recently just bought the bike so I guess anythings possible.

My brother knows alot about bikes and was going to show me all the things I need to do to keep it running well but hes in hospital at the moment and will be outta action for a wee while.
I know the basics - change oil, spark-plugs etc but I know next to nothing about getting a 2-stroke running well (hence my upcoming tutelage).

Me thinks professional help will be necessary as I'm not keen on losing power in the middle of an intersection (its happened once - thankfully I've had to push start some farm bikes before so I can quickly mount/dismount on the run )

So, sounds like it maybe a carbie problem - any ideas what it costs to get it looked at?

Kevin

[Ixion]

well there's ya problem.

Its a 2 stroke.

I decline to comment further.

Passing in silence over the cheap attempt to besmirch the noble two smoker (doubtless occassioned by jealousy at the manifestly superior design of a two smoker) - fact remains it may be sort of right.

Depending on the DEGREE of what you're relating, it may just be par for the course for a very high tuned two stroke. They don't always idle too well, and usually are not happy chappies until good and hot. You aren't going to get the sort of low speed low rev docility that you do with a four stroke.

Why would you want to run it under 4000 rpm anyway ? It's a two smoker - wring its neck.

Change the spark plug. Always a good start on a two stroke. Replace air filter. The only oil you have to change is gearbox oil, BTW. You do NOT change the oil in the oil tank. But it WILL get rapidly used up, cos it burns oil, by design.

Does it smoke the right amount ? Should be a bit of a haze , not none at all, and not a solid cloud.

Carb tune on a two stroke twin shouldn't cost too much - though such statements are always relative. But if it goes strong and revs free when it's hot, it may just be a matter of getting used to a two stroke. remember, it is a near race machine. Lack of docility is the trade off for high power. No free lunches alas.

[Black]

Hi Ixion,

Its not that I don't want to go over 4000 rpm, its that sometimes I can't.
When i start it up it usually dies when I try to give it some throttle.
If I get going then let the revs fall below 4k (like when waiting at an intersection) it dies again.

Once its been running for a while the problem goes away.

I live off a busy street about 1km long with relatively busy intersections at each end. Thus the bike always dies at one of these intersections when I leave home (if I forget to keep the revs above 4k).

It has me flummoxed (which usually doesn't take much )

[Ixion]

Is the 4000 rpm quite specific, and does it cut out clean, or does it splutter out? And how long is "a while". Do you keep the choke on while it's warming up ?

[Pixie]

It's basically an RZ 250 motor.It should idle smooth and run real well.
I assume it has the YPVS of the RZ it may be seized up or the exhaust port may be coked up

[Black]

Hi Ixion,

Is the 4000 rpm quite specific, and does it cut out clean, or does it splutter out? And how long is "a while". Do you keep the choke on while it's warming up ?

I guess I should have said around 4000 rpm, by my observations 4k is about where its all happening but it could be happening anywhere between 3000 & 5000rpm.
The revs climb fast on this beasty and I'm sometimes a little too slow.

When it dies it seems to cut out clean ... no coughs or farts.

I keep the choke on until its warmed up then I turn it off.

Its hard for me to say exactly how long "a while" is ... when I'm moving 30mins seems like 30secs and when I'm kickstarting and having trouble 30secs seems like 30mins.
I guess "a while" is about 2minutes.

Why would you want to run it under 4000 rpm anyway ? It's a two smoker - wring its neck.

Hehe .. yeah, I'm still struggling a little with this, pottling around the farm has given me some hard to break habits.

Does it smoke the right amount ? Should be a bit of a haze , not none at all, and not a solid cloud.

It smokes a lot when I start it up (big beautiful clouds) but once its warmed it doesn't smoke much.

[willy_01]

not sure if this will help but same sort of thing happened to my bike, only dif was the fact i could start it when cold at all. I got sick of using engine start so diceded to have a crack myself. My problem was a leaky carb (i think) i dont know the science behind them too well but i think it was getting starved of fuel at low rpm (due to drop in pressure?) but cleaned them both out (made sure they were sealed well) balanced them and now she starts first ...or second kick every time

Remember 2 strokes arnt unreliable they are just waiting for the 4 strokes to catch up

[Dadpole]

As Ixion says: Check the air filter and plugs. If they are OK then it is probably the carbs. When I got my tzr, the slides were 5mm out of sync. These sorts of things can happen when someone has a fiddle - meaning previous owner.

[Ixion]

Two minutes doesn't seem long to get a two stroke onto song. I'd check the plugs, condition and grade first. Someone may have cautiously put in a very hard plug which is fouling when cold - aggravated by excess oil , which will lean out the mixture, needing lots of choke. The classic two smoker dilemma.Put in a soft plug so that it starts easily and idles nicely, and you blow a hole in a piston. Put in a hard plug to keep the engine safe, and it's a bitch until it gets good and hot. That's two strokes for y'. You really need to change plugs once the engine warms up. Shouldn't smoke too much at start, lots and lots of smoke may indicate either non functioning valves in the oil lines (assuming you're not using premix) or leaking main seals (ouch).

Two smokers are bit like me - tend to be cranky and not perform well first thing in the day. If it goes well when it's hot, there's unlikley to be much wrong.

[GR81]

How much does a service & tune-up usually cost?

My 6000km service cost me $200+/-, but it was only a service and not a fixer.

[Posh Tourer :P]

Where and when do you ride it?

My XJ does something similar, as it runs on 3 for about 10-15 seconds after starting. It also bogs when you rev and you have to be careful when starting. After about 20 seconds this goes away.

It also goes away when you do 900miles in 2 days, rather than commuting very short distances daily.

In other words, are you being too nice to it? Wring it's neck and take it for longer rides than say 15 mins. If you already do this, then perhaps you need to change plug as Ixion says (tho I kow very little about that subject). Short rides without the bike warming up completely will foul the plug and not help the starting process (normally the carbon on the fouled plug needs to warm up to make it go properly).

By warming up completely I dont just mean so that you can take the choke off either. I mean a good long ride....

[HCW]

Asuming you have 2 new (not used and cleaned) NGK B8ES spark plugs, clean air filter, non modified airbox, fresh 91 petrol and good quality 2 stroke oil, it sounds like blocked pilot jets. Remove the carbs, strip and clean all the jets and the carb housing, reassemble it and keep your fingers crossed. Or you can call me on 021 456 568 and I'll take a look.