having some troubles :/

[miggy]

Plug looks better to me. The NGK chart (I'm guessing) would be for 4 stroke engines ie no oil in the mix. Anyway don't think it's weak now.

The apparent obsession with the temp was because I could think of nothing that would permanently damage a new plug (internal arcing) except heat.
If it was heat damage, and the gauge wasn't showing high temp, the gauge / thermistor had to be faulty. Thermistor is also next to plug and may be cooked.

That may seem irrelevant, but the only temp indication we have is the gauge, and we needed to know for sure if the engine was overheating, or not.
Hope that makes sense, I know what I mean, but may not be passing it across too well.

Even then a bit puzzled. the cylinder jacket is watercooled, but is the cylinder head ? No fins and long spark plug thread suggests it may be, but not sure.
Will see what pictures I can find, manual I have is not clear in that area.

The compression reading is low for a high compression ratio engine, but don't think just wear alone would cause overheating,
could be loss of compression due to expansion, but it would need to be pretty drastic to stop a running engine.
If there's ring /bore damage as well, that's another matter

@ Ron, This is just discussion, suggest you ignore above for now. More important to try bike and see what changes, if any.

The engine is running fine for 20 minutes so what could possibly alter in that time?. Something heat related. Do you think it's worth checking the plug lead? the cap has been changed. When cold it's fine but a hot wire especially if its core is made of carbon can become brittle when hot and cause an intermittent spark. Failing that the valves may not be seating properly hence the low compression. Has ron had the cap of the cut of switch and examined the contacts/wires properly?.

 

[miggy]

dan if one of the water galleries was cracked it would let water in to the cylinder and get blasted out of the exhaust port. Is there a hairline crack that gets wider/expands when hot. Is the air filter wet ron?. Do you hear any air hissing anywhere ron is there a vacuum pipe loose or opens up when hot. Is there a crank case breather pipe trapped or cracked?.

 

[big-ron]

The engine is running fine for 20 minutes so what could possibly alter in that time?. Something heat related. Do you think it's worth checking the plug lead? the cap has been changed. When cold it's fine but a hot wire especially if its core is made of carbon can become brittle when hot and cause an intermittent spark. Failing that the valves may not be seating properly hence the low compression. Has ron had the cap of the cut of switch and examined the contacts/wires properly?.

dragging this out now lol, and cant thank you enough miggy and danforth the plug looks the best ive seen it. and ive had 2 new plugs in it. this plug thats in it now is the higher running temp one. think its might/must be a heat thing. as its been said 15-20 mins of running then alway dies, but looking at all the normal things on the bike, no water leaks, temp seems to working fine from what i can from this end, the compression is low as said (only 1000 psi), the wires around the engine are well out the way, so cant see that been a problem. the plug lead is a new one, came with the coil (week half old) so i think the next step is may be take to shop the find out? @£30 ph i think 2 hours should be more than enough to find what going on. thats what im thinking lads.

also just to add i checked the rad bleed screw, when engine running i undone the bleed screw and the water was comming out, which i would expect. the rad pipes feel warm but dont feel as theres much flowing though them, but when sqeeze them, i can see the water/ coolant move up and down in the coolant tank, does that make sense??

ronnie

 

[miggy]

Perhaps you are right ron get the bike in to be tested properly we can only guess what the problem is without looking at the bike. It could be 30.00 well spent if its something simple.

 

[danforth]

The engine is running fine for 20 minutes so what could possibly alter in that time?. Something heat related. Do you think it's worth checking the plug lead? the cap has been changed. When cold it's fine but a hot wire especially if its core is made of carbon can become brittle when hot and cause an intermittent spark. Failing that the valves may not be seating properly hence the low compression. Has ron had the cap of the cut of switch and examined the contacts/wires properly?.

Way back the op was cutting out, after starting, when throttle opened. This has changed now but took several attempts to extract that
info, with brother in law assurances etc. As far as I know ron has changed "cap and coil", that took some clarification as well (read back)
but thought that included HT lead as well. It is looking heat related, pre existing before sale, and understandably causing friction between
ron and brother in law. Don't want to make that any worse, but has to be taken into account with all preceding info.

It's a 2 stroke, no valves. I made that mistake early on too ! If it is a 4 stroke, I'm reading the wrong manual still.
Confusing for me as well. My bike days are mid 60's, 4 stroke, air cooled, twins. I do have recent experience with 2 stroke lawnmowers.
Got involved with the thread, early on when no one else responded, and got interested from there.

The compression test, possibility of engine damage etc is only recently mentioned. Still think we need to know, whether overheating, or not.
Heat related was cracks in inlet manifold, first told about, then not there. Last in that area was cracks in rubber carb/manifold gasket,
but not right through. So, bits of info, we're guessing around.

I'm still trying to get the big picture, but with recent info not looking cheap. Suggest you read through thread, if you have time,
you'll see what I mean. Also another thread when ron first got the bike.

Cross posted again, must speed up my typing !

 

[miggy]

Way back the op was cutting out, after starting, when throttle opened. This has changed now but took several attempts to extract that
info, with brother in law assurances etc. As far as I know ron has changed "cap and coil", that took some clarification as well (read back)
but thought that included HT lead as well. It is looking heat related, pre existing before sale, and understandably causing friction between
ron and brother in law. Don't want to make that any worse, but has to be taken into account with all preceding info.

It's a 2 stroke, no valves. I made that mistake early on too ! If it is a 4 stroke, I'm reading the wrong manual still.
Confusing for me as well. My bike days are mid 60's, 4 stroke, air cooled, twins. I do have recent experience with 2 stroke lawnmowers.
Got involved with the thread, early on when no one else responded, and got interested from there.

The compression test, possibility of engine damage etc is only recently mentioned. Still think we need to know, whether overheating, or not.
Heat related was cracks in inlet manifold, first told about, then not there. Last in that area was cracks in rubber carb/manifold gasket,
but not right through. So, bits of info, we're guessing around.

I'm still trying to get the big picture, but with recent info not looking cheap. Suggest you read through thread, if you have time,
you'll see what I mean. Also another thread when ron first got the bike.

Either way mate there is not much more we can advise now. It really needs specialist testing equipment on it to successfully diagnose the problem. Guessing at this stage could become very costly. My biking days were in the late 70's I had quite a few bikes then. It will be interesting to see what the full diagnosis is going to be. Keep us informed ron.

 

[big-ron]

Either way mate there is not much more we can advise now. It really needs specialist testing equipment on it to successfully diagnose the problem. Guessing at this stage could become very costly. My biking days were in the late 70's I had quite a few bikes then. It will be interesting to see what the full diagnosis is going to be. Keep us informed ron.

i will lads, i will phone up tomorrow to see if can get her in over the weekend, fingers crossed its not to much, im willing to spend about £200-300 pound as i will get money back at a later date. im trying to explain the problems with bike as they happen and what i have been told, sorry if i have confused you both :/

 

[miggy]

i will lads, i will phone up tomorrow to see if can get her in over the weekend, fingers crossed its not to much, im willing to spend about £200-300 pound as i will get money back at a later date. im trying to explain the problems with bike as they happen and what i have been told, sorry if i have confused you both :/

You havent confused us ron lets just say we like to get involved and try to help. All we want to know now is exactly what is wrong with your bike. I hope I speak for dan on this as well by saying it has certainly been an interesting thread. Good luck ron.

 

[danforth]

i will lads, i will phone up tomorrow to see if can get her in over the weekend, fingers crossed its not to much, im willing to spend about £200-300 pound as i will get money back at a later date. im trying to explain the problems with bike as they happen and what i have been told, sorry if i have confused you both :/

Don't worry about that Ron. You admitted at the beginning you knew little about bikes. Sorry, but it seems your bother in law
didn't know much more either, except for riding them.

See what the pro's have to say, the bay ad that miggy gave you looked good value, if it comes to that, so will give you some idea about any estimate they give you.
Changing the barrel, piston etc is not too difficult, but you may need special tools, and it's a long winded job without prior experience.
Certainly not something to be tackled "first time out".

Good luck, let us know !

 

[big-ron]

Quick update, bile going in this Wednesday. Will keep you both posted.

 

[muskrat]

Hi fellas,

Just a quick thought from my biking days, you say the bike was stood a while, it might sound daft but try changing the feed pipe for the petrol, the one from the tank to the carb, I had the same problem years ago and it was due to a weak feed pipe getting warm and 'nipping closed' and killing the fuel flow to the carb. May be bollox but for a couple of bob you could eliminate one more possible.

Best wishes and good luck mate.

B

 

[jondoe]

have you checked the 2 stroke oil side of things.. pump,,, cable,,, is there 2 stroke oil in it,, is it contaminated eg water sitting in pipe

 

[big-ron]

have you checked the 2 stroke oil side of things.. pump,,, cable,,, is there 2 stroke oil in it,, is it contaminated eg water sitting in pipe

change all that mate, out of my hands now its go to the bike shop and still waiting to find out whats going on? phoned up today but they said they have NOT looked at it yet. been in from wednesday 11am.

 

[miggy]

change all that mate, out of my hands now its go to the bike shop and still waiting to find out whats going on? phoned up today but they said they have NOT looked at it yet. been in from wednesday 11am.

Ffs ron they are not charging by the day are they?. 3 days is long enough to find a problem surely. Keep us informed ron.

 

[eddyplumber]

could be smallest piece of dirt which is blocking at times flush all out and start again filter fuel throught ladies tights also filter when refuelling best of luck

 

[big-ron]

Ffs ron they are not charging by the day are they?. 3 days is long enough to find a problem surely. Keep us informed ron.

hi miggy and danforth, final an up date, phoned up today again to find out whats going on, and the man said i need an exhaust as its blocked????, so the only thing that could block it, is the rave valve in side the exhaust , which i think can be removed. if i remove it? what would it do to the bike? he set up the carb & changed the main jet,he also said it was cutting out after 15-20 min, that when he said about the exhaust.




im looking it the manual as i type this, i have have a look around for an exhaust cant seem to find one on flybay.

 

[danforth]

hi miggy and danforth, final an up date, phoned up today again to find out whats going on, and the man said i need an exhaust as its blocked????, so the only thing that could block it, is the rave valve in side the exhaust , which i think can be removed. if i remove it? what would it do to the bike? he set up the carb & changed the main jet,he also said it was cutting out after 15-20 min, that when he said about the exhaust.


View attachment 73183

im looking it the manual as i type this, i have have a look around for an exhaust cant seem to find one on flybay.

Hi Ron,

Just a quick reply, to show we're still here. Seem to remember the rave valve was a "race" thing and not allowed fitted in some countries.

Suggests it can be removed (presumably reducing performance) but will check later and come back.

 

[miggy]

The only thing I could find so far ron is this one. Aprilia RS125 NEW Power Valve Housing Body Powervalve Exhaust RS 125 122 123 RX | eBay

Or this
APRILIA RS125 MX RX power valve servo unit | eBay

 

[danforth]

I've read the rave section of the manual a couple of times, and can't see what it actually does, my fault probably.
Opens 500-2500 (stem cleaning) 2550-8000 (closed) over 8000 (open). Unless it's jamming from heat (or ecu malfunction) after 20 mins, can't see relevance.
Since a rave valve can be retro fitted, guessing it can run without it, at reduced performance, and does so in some countries.
Ignoring the stem cleaning bit, it's shut below 8000 anyway. Retro fitting mentions removing a "slide" (guessing a blanking plate) at the start,
so imagine that's an option, if only to prove where the fault lies.

Cleaning, or changing, looks straightforward and shouldn't be too expensive, bearing in mind miggy's link, even if done by a pro.
Diagnosis, to me sounds iffy, but as said, I know nothing about rave valves, and that's what pro's are for.

Suggest you contact the dealer and see if they will clean / change it on a "no win no fee" basis, labour only if it makes no difference.

Any thoughts miggy ?

 

[danforth]

Another thought, for what it's worth.

We know it starts and runs ok for 20mins or so.

When cold, how about disconnecting the wire between solenoid and ecu, and see whether it starts and keeps running ?
Should disable the rave valve, and indicate whether it's the problem, without much dismantling.