Page 2 of 2
Re: gearing
Posted: 17 Sep 2023 11:18
by budge
Steve Brown wrote: 16 Sep 2023 22:09
Oh dear, that isn't sounding positive. I will have a spare valve adjuster assuming your rockers etc are ok-mind you, I might have rockers to spare too. Don't get too despondent, these engines are fairly easily worked on and fixed if you can find the parts. And the parts are mostly available too. Let us know what you need and I'm sure you'll be able to sort the problems.
Hi Steve and thanks for the reply, not sure how hard it will be to get a new adjuster and it will need a rocker as it has play. I did have a look on eBay but nothing in the UK and only full sets from Italy so good to know you may be able to help out, Thank you. I am already enjoying riding the bike so not going to get despondent and it will run as it should eventually.
Thanks again, Budge.
Re: gearing
Posted: 17 Sep 2023 16:18
by mbmm350s
Hi
The rocker arm bushes and shafts are often worn, that won't stop them running, might well add to the general clatter.
The non captive rocker should only have a little end float like 0.1mm, so shaft might need pushing through.
Mdina Italia in the UK might even have new ones, or second hand. Dont forget to claim your MRC discount.
how are the valves sealing?
+1 For they still run ok with broken rings
Mark
Re: gearing
Posted: 17 Sep 2023 20:46
by budge
72degrees wrote: 17 Sep 2023 06:15
What Steve said. I have spare rocker gear. It might just be in need of rings on the bad cylinder, though in my experience they will run surprisingly well with at least the oil control rings in multiple pieces. was there much coming out of the crankcase breather ?
Hi and thanks for the reply, no I can't say much was coming from the breather but I haven't done that many miles on the bike, everything looks good in the cylinder apart from a thick black ring of carbon at the top of the cylinder but not sure if it is carbon or remains of gasket compound that someone has used in excess on the head and base gaskets and not sure it should have been used at all with the alloy gaskets. It is good to know that people have spares that they are willing to part with, I will have a look and see if I can find some spares before I start using up other people's spare parts but I may get back to you on that one.
Many thanks again, Budge
Re: gearing
Posted: 17 Sep 2023 20:55
by budge
mbmm350s wrote: 17 Sep 2023 16:18
Hi
The rocker arm bushes and shafts are often worn, that won't stop them running, might well add to the general clatter.
The non captive rocker should only have a little end float like 0.1mm, so shaft might need pushing through.
Mdina Italia in the UK might even have new ones, or second hand. Dont forget to claim your MRC discount.
how are the valves sealing?
+1 For they still run ok with broken rings
Mark
Hi Mark and thanks for your input, I would say the end play is more than 0.1mm and the upwards play is about 0.1mm, I haven't had a chance to take the valves out yet but nothing looks bad with them in place.
Thanks again, Budge.
Re: gearing
Posted: 02 Oct 2023 20:12
by budge
Re: gearing
Posted: 02 Oct 2023 21:14
by budge
Re: gearing
Posted: 03 Oct 2023 11:10
by Steve Brown
Sorry I can't explain the dots or be sure about the number 2. I would personally disregard the dots as either damage from debris in the past or some previous owners marking to keep parts from a particular cylinder together. The spring under the oil ring is as you've read, only for older type pistons so wouldn't be expected on yours.
Measure the bore properly and you'll soon see if it has been rebored and determine the oversize.
What I can see though is a fair bit of carbon suggesting a reasonable mileage covered and potential wear associated. If the bores are not too worn a simple re-ring of the pistons, hone the bores and clean and lap the valves in etc should be enough. Obviously the bore wear needs to be assessed first.
Looking at the cylinder head the spark plug looks a long way up the hole. Is it partially unscrewed? Or is it the wrong type? In the NGK range you want a BP6 or 7 ES. The P and the E in the code are important to get the spark in the right area.
Re: gearing
Posted: 03 Oct 2023 13:33
by MickeyMoto
Was it burning oil? How are the valve guides?
Re: gearing
Posted: 03 Oct 2023 14:14
by mbmm350s
The 2 marking is for oversize, meaning 0.2mm or first oversize, measurements would confirm this.
I reckon the dots were made by a "mechanic" to keep parts together as Steve says.
Mark
Re: gearing
Posted: 03 Oct 2023 15:08
by budge
Steve Brown wrote: 03 Oct 2023 11:10
Sorry I can't explain the dots or be sure about the number 2. I would personally disregard the dots as either damage from debris in the past or some previous owners marking to keep parts from a particular cylinder together. The spring under the oil ring is as you've read, only for older type pistons so wouldn't be expected on yours.
Measure the bore properly and you'll soon see if it has been rebored and determine the oversize.
What I can see though is a fair bit of carbon suggesting a reasonable mileage covered and potential wear associated. If the bores are not too worn a simple re-ring of the pistons, hone the bores and clean and lap the valves in etc should be enough. Obviously the bore wear needs to be assessed first.
Looking at the cylinder head the spark plug looks a long way up the hole. Is it partially unscrewed? Or is it the wrong type? In the NGK range you want a BP6 or 7 ES. The P and the E in the code are important to get the spark in the right area.
Thanks for your reply Steve, the dots are probably from some previous rebuild as you say so disregarded, good to know an oil ring spring is not required and isn't something that had been forgotten at a previous rebuild, the carbon you see is I suspect mostly burnt excess gasket compound, it was everywhere and I think it had got to the rings and seized them, I can't say it is correct but according to the clock it has done 41000k. The spark plugs are the correct plugs but not fully home. Thanks again for your help, Budge.
Re: gearing
Posted: 03 Oct 2023 15:14
by budge
MickeyMoto wrote: 03 Oct 2023 13:33
Was it burning oil? How are the valve guides?
Hi Mickey, mostly excess gasket compound I think, I have never seen so much gasket compound used to put a cylinder head gasket on before. The valve guides are good.
Thanks, Budge.
Re: gearing
Posted: 03 Oct 2023 15:23
by budge
mbmm350s wrote: 03 Oct 2023 14:14
The 2 marking is for oversize, meaning 0.2mm or first oversize, measurements would confirm this.
I reckon the dots were made by a "mechanic" to keep parts together as Steve says.
Mark
Hi Mark and thanks for your help, I thought the 2 was for oversized but thought it was for 2nd oversize, I agree with you on the dots.
Thanks, Budge.
Re: gearing
Posted: 24 Oct 2023 18:58
by budge
Update, but first I would like to thank everyone who commented and tried to help with suggestions. At last, I have found the problem and the bike is running 98% better (it just needs some fine-tuning now) after trying all the suggestions the only thing I hadn't tried was what Paul Compton suggested in one of his videos on Dell Orto carbs, he said that the 260K needle jet (atomizer) might need replacing with the 260 D OR 260 BD but the D and BD are hard to get, the K can have more holes drilled to make it into a D or BD, when I looked at Euro Carbs website to see where to drill the holes I found that someone had been there before me and the holes had been drilled, I ordered a new set of 260Ks (ordered from Euro Carbs on Sunday evening and here this lunchtime, Tuesday) and the bike is going so much better. Thanks again to everyone and Paul Compton for the videos, Budge.
