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Aarron

Joined:

Oct 10

Posts: 20

Aarron says:

Aprila Rs 125- Exausht Problems

Hi all,

I totally understand the fact that the Rs125 is a 2stroke and smokes but shouldn't be smoking this much.

I have been looking about and found a thread where it looks like I'm having the same problem, when I get the bike to around 40mph - up/ 7k it smokes like hell, I first thought it was the choke cable but wasn't, it's not seeping from the bottom of the can, it's just purly comming from the end of the can and it's a 'Blue'

The oil/fuel mixture seem's fine and is set at what it say's, but it's still smoking, I've been told it could be the gaskets ? they could be worn thus allowing oil to seep through?

Just thought i'd ask on here before I go and take it to a bike shop I'd try and fix it myself but as I need the bike on a daily basis for work I can't afford to break something thus causing me to have to wait 3 or 4 weeks before a part get's fixed.

(The last owner did nothing with it just let it sit in the back garden/ never looked/ replaced anything (maintained) it, so I understand I'm picking up the pecies but it's a decent bike and justt want it to work and last me untill November & I understand it's going to cost me money as she didn't spend a penny on it.)

Thanks for any help. 

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  • Posted 3 years ago (10 May 2011 17:00)

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littleredrooster

Joined:

Aug 02

Posts: 467

Smoke

It may just need a good long run at high revs to burn off whatever is in the can. Two-strokes which are pottered about too much tend to oil up like this, and a good thrash usually sorts them out.

Try a 10-20 mile dual-carriageway ride and keep it pinned!

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littleredrooster

Joined:

Aug 02

Posts: 467

Smoke

It may just need a good long run at high revs to burn off whatever is in the can. Two-strokes which are pottered about too much tend to oil up like this, and a good thrash usually sorts them out.

Try a 10-20 mile dual-carriageway ride and keep it pinned!

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smoto5

Joined:

Mar 09

Posts: 4586

smoto5 says:

First question is

what oil are you using in the oil tank (not the gearbox oil, sorry, some people do get confused between the two, as many four strokes have combined engine and gear oil), anyway, you should be looking to use a very high quality grade suitable for injector systems and not a premix type oil or the budget ones from the car garage/supermarket etc. (the better ones can often be described as a low smoke type as well). It is well known that the Aprilias don't do too well on basic oil and can get problems, especially in the hands of younger learners. 

Hopefully you are not getting problems with oil being drawn from the gearbox/clutch casing  through the oil seal on the crankshaft on that side, this may happen after an extended mileage, but usually accompanied by some air being sucked through the seal on the ignition/magneto side of the engine, it's part of two stroke repair and rebuild that these can need replacement eventually.  What sort of mileage does the bike have on it? Standing for extended periods of time can sometimes cause the seals to harden, but less so in this day and age. It is possible in many cases to change those seals without a full engine strip down.
It's not usual to find wear in the piston and cylinder bore causing blue smoke to the extent that it would in a four stroke.

 Hopefully though some higher rev running will cure the problem as suggested, :smile

[This Reply has been modified by the Author]

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Aarron

Joined:

Oct 10

Posts: 20

Aarron says:

answers

I will try the Motorway as there aren't many decen't long dual-carridgeways where I live.

as for oil, I'm using Castrol 2T simply because my boss used it when he had the bike (Many Years Ago) and told me what oil's/ fluids to use.

no oil is comming from the crankshaft just burning a thick(ish) blue from the exausht.

The bike has been running fine since September had new Clutch Cable, New Ballance Shafts, Front Bearing's, Front Tier & Pads.

But this has come recently I have never had this problem with the bike before and i use it on a daily basis like I said so it's just sprung on me really last weekend I thought it was just a build up but it's just started to happen and i've been riding before and after it's doing this.

(That's why I thought it could be the gaskets or a scratched piston?)

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smoto5

Joined:

Mar 09

Posts: 4586

smoto5 says:

According to Castrol website

you should be using Power 1 TTS 2t oil in an RS125, if you are only using the basic 2t I would switch over as soon as possible. Back when I had an Aprilia 125  they recommended Elf oils, was a bit hard to find though, so I usually used Silkolene or Putoline Race oils, as long as they were suitable for oil injection systems, the premixes tend to be a slightly thicker grade. Realistically any decent make of high performance race type oil is suitable as long as it's for injection, the basic grades are only really any good for commuter bikes and garden equipment or as an emergency measure at lower throttle and minimum load (previous owner of mine had managed to seize it up, several times!) Anyhow, good luck, hope you get sorted ok :smile

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littleredrooster

Joined:

Aug 02

Posts: 467

Smoke

Aarron said:
"no oil is comming from the crankshaft just burning a thick(ish) blue from the exausht."
Where would oil be 'comming from the crankshaft'? Not sure what you mean?

Aarron said:
The bike has been running fine since September had new Clutch Cable, New Ballance Shafts, Front Bearing's, Front Tier & Pads.

What relevance does this have to the current problem? What are new 'ballance shafts'?

[This Reply has been modified by the Author]

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eatcs01

Joined:

Aug 02

Posts: 3222

eatcs01 says:

oil

I think he means crankCASES. If the crank seals fail, then the oil from the crankcase will find it's way into the combustion chamber.



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smoto5

Joined:

Mar 09

Posts: 4586

smoto5 says:

I think he may just be

trying to point out that he has looked after the bike properly since having it, in fact the present problem may or may not have anything to do with him, it may date back to the previous owner, certainly the previous owner of my Aprilia had managed to seize it up on a number of occasions (at least partly) judging by the damage to the piston (but that was a much older model)

The smoking can be from a few different causes of course, as said a build up of oil from low speed running, particularly if oil pump setting is wrong, wrong type of oil, sucking oil through the crankshaft seal from the clutch side (gearbox oil) into the crankcase where it gets mixed up with the petrol and injected oil and therefore too much oil, causing smoking. It's even possible for the seal to between the two crankcase halves to be defective, particularly if the engine has been stripped/split and rebuilt, some bikes have a gasket between, some have just gasket sealant, all need a good mating surface free of blemishes and damage between the two, any small gap can let oil in from the gearbox or air from the outside. Aprilia have in the past recommended adding oil to the fuel in the tank when setting the oil pump, to ensure the engine has oil in the meantime, at other times it should be just straight fuel, has he changed garage where he fills up? contamination in fuel? Diesel in storage tank at garage before the petrol? 

Aarron, can you post more exact history of the bike? servicing repairs/rebuilds etc. it's possible there is a balancer shaft in the engine, but it's a bit unusual on a small two stroke. Also could you post a link to the thread about a similar problem?

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