T140V 1976 Composite Gasket

[Migsan]

Just to post an update!
Got all of these instaled. Must say the mushrom head tappets make the engine sound smoother. Allready retorqued the head after the 1st 5 miles ride. Still having fouled plugs. Checked the barrels with the endoscope there is still what appears some oily residue on the piston but far less than before. Took the bike on the highway and did aproximately 40 miles around 60 MPH to try and burn any residue. wasnt running great plus had to exchange the plugs halfway!
I had the carbs resleeved and with new screw in pilot jets. All the remaining parts were new and acording to spec. I rechecked and the needle holder is on the higher groove and mixture screw is 1.5 turns out. Floats should be as instructed as well. Shouldn´t be running rich! Took it for a ride today to the gas station after cleaning the plugs. It's now booging! This bike got me scratching my head again!
What do you think @solomon?

 

[solomon]

I don't know! Maybe people can help dissect this.

First thing is, which is it causing fouling? Running rich or oil?

After turning the needle out 1.5 turns, did you then tune the carb, i.e., adjust mixture and stop screws to obtain best running idle (doing that when the engine is hot, not cold)?

Why is needle on higher groove? Would normally start off with it in middle groove.

 

[Migsan]

I don't know! Maybe people can help dissect this.

First thing is, which is it causing fouling? Running rich or oil?

After turning the needle out 1.5 turns, did you then tune the carb, i.e., adjust mixture and stop screws to obtain best running idle (doing that when the engine is hot, not cold)?

Why is needle on higher groove? Would normally start off with it in middle groove.

yeah tuned when it's hot! yes I then try to tune the carb using the mixture and stop screw set it to 1000 to 1100 rpm. Usually the mixure screw is set between 1.75 to 1.25 turns out. I can put the needle in the middle grove. I just placed it on the higher position to make sure it was the leanest.
Fouled plugs alone can cause that booging?

thanks

 

[solomon]

Fouled plugs alone can cause that booging?

What's booging,? Do you mean bogging, as in sluggish?

Are the plugs sooty (matt black) or oily (shiny black)?


You say it's had an engine rebuild, and has good compression. It has new valve guides. It has a new pump. Maybe a bit of dirt is stuck in the pump. It relatively easy to clean and test the pump. New pump isn't necessarily a good pump...

Is there oil in both cylinders? Makes it less likely it's rings if so?

 

[Migsan]

What's booging,? Do you mean bogging, as in sluggish?

Are the plugs sooty (matt black) or oily (shiny black)?


You say it's had an engine rebuild, and has good compression. It has new valve guides. It has a new pump. Maybe a bit of dirt is stuck in the pump. It relatively easy to clean and test the pump. New pump isn't necessarily a good pump...

Is there oil in both cylinders? Makes it less likely it's rings if so?

Hi Solomon
I undestood booging is when the bike doesn't respond to the throttle and instead starts gasping like if there was a fuel cut or something.
Plugs are matt black. The oily residue is seen on both barrels like the picture I posted. Could it be rests of carbon and gas residue?
Good compression 150 psi both barrels.
I will recheck the pump. When you mention the pump would be if there was an issue with the return? Would that cause acumulation on the sump?
I am able to see good flow on the return.
Thanks

 

[solomon]

Hi Solomon
I undestood booging is when the bike doesn't respond to the throttle and instead starts gasping like if there was a fuel cut or something.
Plugs are matt black. The oily residue is seen on both barrels like the picture I posted. Could it be rests of carbon and gas residue?
Good compression 150 psi both barrels.
I will recheck the pump. When you mention the pump would be if there was an issue with the return? Would that cause acumulation on the sump?
I am able to see good flow on the return.
Thanks

Ok, never heard of booging. Led a sheltered life.

If it's richness, must be carbs. Tuning not correct, or jets worn maybe. You've tried hotter plugs, and new and correctly gapped plugs.

If it's oil, you've eliminated valves and head gasket.

So it's eliminating other things.

What is a good return on oil? The return has to be comfortably that of what's going into sump.

You've checked pump? Have you done a bench test, checked it's suction is good?

 

[solomon]

Plugs are matt black. The oily residue is seen on both barrels like the picture I posted. Could it be rests of carbon and gas residue

Do you mean is the oil in cylinder in fact fuel? It would evaporate almost instantly if fuel?

If oil, must be being replenished, otherwise wouldn't be there after a run?

 

[triumph david]

Are you sure the oil is draining out of the cyl. head and not building up around the top of the valve guides?

 

[solomon]

View: https://m.youtube.com/watch?v=mPDJnChqXys

 

[Migsan]

Do you mean is the oil in cylinder in fact fuel? It would evaporate almost instantly if fuel?

If oil, must be being replenished, otherwise wouldn't be there after a run?

I see what you mean @solomon so if it was just from richness it shouldn't leave any residue. Also worth mention my oil level been pretty constant I would say.
I can check the pump just be sure. In regards of the pump return out put if it wasn't beeing efficient wouldn't I have more oil in the sump than the 150ml or 1/4 pint?
@triumph david there os definitely much less oil than before replaced the valves and valve guides. The new intake valve guides have the seals. How could I check if oil is filling up the cyilinder head? Running the engine without the ispenction caps?
Thanks

 

[solomon]

I've never done a leak down test. Haven't had a compressor all that long.
Would let you know if there's an issue with valves sealing, or head gasket leaking.


View: https://m.youtube.com/watch?v=rZ8iDHice0E

 

[solomon]

In regards of the pump return out put if it wasn't beeing efficient wouldn't I have more oil in the sump than the 150ml or 1/4 pint

Yes, you're probably right. But something is up. It's a process of elimination if there's no obvious answer. It not really a waste of time checking pump, it'll be one more thing you're confident is good.

 

[Migsan]

I don't know! Maybe people can help dissect this.

First thing is, which is it causing fouling? Running rich or oil?

After turning the needle out 1.5 turns, did you then tune the carb, i.e., adjust mixture and stop screws to obtain best running idle (doing that when the engine is hot, not cold)?

Why is needle on higher groove? Would normally start off with it in middle groove.

yeah tuned when it's hot! yes I then try to tune the carb using the mixture and stop screw set it to 1000 to 1100 rpm. Usually the mixure screw is set between 1.75 to 1.25 turns out. I can put the needle in the middle grove. I just placed it on the higher position to make sure it was the leanest.
Fouled plugs alone can cause that booging?

thanks

I've never done a leak down test. Haven't had a compressor all that long.
Would let you know if there's an issue with valves sealing, or head gasket leaking.


View: https://m.youtube.com/watch?v=rZ8iDHice0E

That's a great video! @solomon thanks
Don't have the tester or the compressor. might find a mechanic nearby that has one when I return back home in 2 weeks and I shall let you know.
After I instaled the valves/valve guides I tested with petrol and had no leakage but of course under pressure is more realiable. Shall test the pump as well

 

[solomon]

Fouled plugs alone can cause that booging

I don't know. Obviously a spark is inhibited with a fouled plug. Opening the throttle will make the mixture leaner, I think. There's a change of pressure, making sparking 'harder', I think too.
Could be the jets. Have you tested them using the ¼, ½, ¾, and full, throttle positions?

I got one of these...

Used it to remove a sludge trap I'd tried removing for over a year on and off. Use it to blow dry bike after washing it. Will respray in the future. Don't get a piston compressor, they are obscenely loud. Got one of those, luckily had a fault and could send it back.

The pressure testing kit costs £20 on eBay.
.

It's frustrating not knowing what's wrong with your bike. I've had lots of problems, all eventually resolved by process of elimination.

What about carb float heights? Perhaps they are causing some flooding, richness?

 

[Rudie]

Opening the throttle will make the mixture leaner, I think.

No, richer, or the engine would never accelerate.

Could be the jets. Have you tested them using the ¼, ½, ¾, and full, throttle positions?

What @solomon means is:-

. mark the twistgrip housing where you can see the mark when riding the bike;

. mark the twistgrip beside the housing mark corresponding to throttle closed, 1/4 open, 1/2 open, 3/4 open and fully open;

. go for a ride; when the "booging"/bogging starts, note the rpm and the twistgrip position;

. change gear; if the "booging"/bogging persists, again note rpm and twistgrip position; repeat for as many gears as possible;

. if the "booging"/bogging occurs at the same rpm irrespective of twistgrip position, the problem is more likely electrics/vibration related;

. if the "booging"/bogging occurs at the same twistgrip position irrespective of rpm, the problem is more likely carburation related.

 

[Migsan]

No, richer, or the engine would never accelerate.


What @solomon means is:-

. mark the twistgrip housing where you can see the mark when riding the bike;

. mark the twistgrip beside the housing mark corresponding to throttle closed, 1/4 open, 1/2 open, 3/4 open and fully open;

. go for a ride; when the "booging"/bogging starts, note the rpm and the twistgrip position;

. change gear; if the "booging"/bogging persists, again note rpm and twistgrip position; repeat for as many gears as possible;

. if the "booging"/bogging occurs at the same rpm irrespective of twistgrip position, the problem is more likely electrics/vibration related;

. if the "booging"/bogging occurs at the same twistgrip position irrespective of rpm, the problem is more thalikely carburation related.

That's a nice compressor @solomon!
The main jet, neddle jet, pilot jet and neddle were all new. The float I set it like on my commando wich is running fine so I believe it's correct!
Thanks for the explanation on the throttle valve openings @Rudie I never understood how to check it! Is the amal tunning guide for that purpose. I mean the wheel cut out?
Boggging not booging got it!
I shall test all of that when I return!

 

[Migsan]

That's a nice compressor @solomon!
The main jet, neddle jet, pilot jet and neddle were all new. The float I set it like on my commando wich is running fine so I believe it's correct!
Thanks for the explanation on the throttle valve openings @Rudie I never understood how to check it! Is the amal tunning guide for that purpose. I mean the wheel cut out?
Boggging not booging got it!
I shall test all of that when I return!

Hi everyone
So followed the recomendations has instructed. Rechecked the float bowl level. MArked the throtle with the valve openings. placed a new set of spark plugs and off I went. Bike runned perfect the first 10 miles. Nothing at all but after that the same symptoms started to happen specially when I got pinned behind a car and had to go a bit slower. Still got me home. With that said I would conclude that there is nothing electric or carburation/jets related would you guys agree? Removed the spark plugs again all fouled. Checked both barrels with the endoscope still oil residue worst on the right side. inlet valves appeared nice and clean so believe that part was sorted with the new guides and valves.
Decided to remove the head and barrels to try and get to the bottom of it.
Gasket again appeared nice and dry. barrels were full of oil residue on top. Removed the barrels to check the piston/rings. All the gaps apeared to have moved and were now almost lined up specially on the right side. Is that normal ocorrency or that means there are other issues?
Didn´t had time to measure the ring gaps or the barrels but intend to do so when I return home.
Was thinking on replacings the rings regardless and hopefully all the rest will be in spec.
Any recomendations on the piston rings to get? Are GOETZE worth the extra money?

Cheers
Miguel

 

[solomon]

Rings find their own positions. Don't think there's much that can, or need, be done about that.

Hone the cylinders. I bought a three-legged tool, very easy to use, just don't get carried away!

Few hundred miles ago I fitted HEPOLITE rings. Work as intended, no issues.

Don't forget, you need to run engine in if fitting new rings. I could tell you the method I used, although there's probably no right way, but definitely a wrong way.

 

[Migsan]

Rings find their own positions. Don't think there's much that can, or need, be done about that.

Hone the cylinders. I bought a three-legged tool, very easy to use, just don't get carried away!

Few hundred miles ago I fitted HEPOLITE rings. Work as intended, no issues.

Don't forget, you need to run engine in if fitting new rings. I could tell you the method I used, although there's probably no right way, but definitely a wrong way.

Hi @solomon But if that's so in regards to the rings why do we go to the trouble no place the gaps the further away from each other?
Do you recomend the use of break in oil?
I was thinking about just honing with sand paper lightly to remove the glaze any thoughts on that?

 

[solomon]

Hi @solomon But if that's so in regards to the rings why do we go to the trouble no place the gaps the further away from each other?
Do you recomend the use of break in oil?
I was thinking about just honing with sand paper lightly to remove the glaze any thoughts on that?

You can't stop the rings finding their own 'place'. Setting them 120⁰ apart initially might see them staying there; maybe crossing fingers would help.

I didn't use break in oil, but changed regular mineral oil after 50 miles; most wearing of metal presumably happens straight off. Don't use synthetic, it's too slippery, rings won't bed in so well.

The tool I bought was this...

https://www.ebay.co.uk/itm/25405733...vMlBMwqTL-&var=&widget_ver=artemis&media=COPY
More likely to get an even distribution of pressure compared to sanding with fingers? Fitted to a battery drill. Took a few seconds to do, moving up and down. Watch YouTube vids beforehand.

Gave an excellent finish.

Thoroughly wash cylinders afterwards!