Here we go again - Page 4

utopia · 25-03-2015, 02:30 AM

I was just thinking today that, with that frame and engine colour, your most likely choices for the tank would be either red or white.
In which case I was rather hoping that my old tank would become white, as I'm not a big fan of red.
But the silver titanium option sounds perhaps even better.
It matters not really, I suppose, but nevertheless I'm pleased.

I thought the tank was decent inside.
For information, since I've had it (which has been nearly always) its been kept largely empty over winter but, crucially in my opinion, in an UNHEATED shed with good ventilation.
Its good to know that the strategy seems to have worked.
Downside is I freeze my nuts off in there when that cold east winter wind blows !

My thoughts on the rose joints was not so much that there might be insufficient thread engagement but more that the end of the hoop was now effectively a lengthy bit of fairly thin threaded rod.
Probably not a problem unless maybe the joint gets stiff, in which case it'd perhaps only hasten a failure that would happen anyway.
But the stress-raising effect of the vee thread, over that extended length, it just kind of caught my eye.

25-03-2015, 06:07 AM

Quote:

Originally Posted by utopia

My thoughts on the rose joints was not so much that there might be insufficient thread engagement but more that the end of the hoop was now effectively a lengthy bit of fairly thin threaded rod.
Probably not a problem unless maybe the joint gets stiff, in which case it'd perhaps only hasten a failure that would happen anyway.
But the stress-raising effect of the vee thread, over that extended length, it just kind of caught my eye.

That is a more reasoned explanation than mine which would have been - would it not be better to use the hoop extenders than use the maximum adjustment on the thread.

Dirty · 25-03-2015, 08:53 AM

Quote:

Originally Posted by DrD

That is a more reasoned explanation than mine which would have been - would it not be better to use the hoop extenders than use the maximum adjustment on the thread.

Do both to get max extension

25-03-2015, 10:56 AM

I,m not a lover of Rose joint extenders to be honest, but these that I have fitted are the McGill version which have a longer threaded part than the originals anyway, which is what Utopia spotted ( as engineers do )

25-03-2015, 01:38 PM

You ever up for visitors from across the border? My bikes ages away from the road but it would be great to stand around in a garage talking bike

Dirty · 29-03-2015, 07:53 PM

Quote:

Originally Posted by Dookbob

I,m on my thirteenth Ducati now, I have fitted filters on the cranckcases of all of them, havn,t had a problem yet, same with the air box, thats the first thing that has to go.

Dookbob can you show me what I need to fit a filter like that. I was in 2 minds about doing it but having just refitted the catch tank and needing a hammer and some swearing I decided to go the filter route

29-03-2015, 10:05 PM

Just go on EBay and search for crankcase breather filter, measure the diameter of the breather stub first because they come in various sizes. Also, if you are still running with the air box you will need a rubber bung for the hole that the catch tank hose used to attach to.

utopia · 29-03-2015, 10:32 PM

I notice that you've put a nice polish on the inlet stubs.
I'm very likely to do the same someday.
Now, I realise that the difference it makes is miniscule but, just for interest's sake, what are your thoughts on whether the shiny surface is better for the carburation, or worse.
My thoughts are that it may well be better, as the polished surface would absorb less engine heat than the original, slightly matt finish ( thus keeping the mixture cooler).
If the shine makes it worse though, even by a tiny amount, then I probably wouldn't bother.
Shiny is nice, but not at the expense of efficiency. That would be sacrilege really.

Dirty · 29-03-2015, 10:35 PM

Quote:

Originally Posted by Dookbob

Just go on EBay and search for crankcase breather filter, measure the diameter of the breather stub first because they come in various sizes. Also, if you are still running with the air box you will need a rubber bung for the hole that the catch tank hose used to attach to.

Cool, thanks. Yes still with airbox for the moment. That will change, hopefully later in the summer.

gary tompkins · 30-03-2015, 02:44 AM

I think 19mm is a common size for many of the breather outlets

But it's a good idea to check it first

http://www.ebay.co.uk/itm/19mm-Engin...item2edeff3107

30-03-2015, 09:38 PM

Quote:

Originally Posted by utopia

I notice that you've put a nice polish on the inlet stubs.
I'm very likely to do the same someday.
Now, I realise that the difference it makes is miniscule but, just for interest's sake, what are your thoughts on whether the shiny surface is better for the carburation, or worse.
My thoughts are that it may well be better, as the polished surface would absorb less engine heat than the original, slightly matt finish ( thus keeping the mixture cooler).
If the shine makes it worse though, even by a tiny amount, then I probably wouldn't bother.
Shiny is nice, but not at the expense of efficiency. That would be sacrilege really.

I think that the polished finish probably will reduce the cooling effect on the fuel intake, but as you say, it will probably be miniscule, truth is I just couldn,t resist doing them. The truth also is that these were the worst inlet tubes I have ever seen, they must have been removed from the mould and thrown straight onto the bike. The amount of metal I had to remove to get rid of the casting marks will probably balance out the drop in cooling effect. I once polished the crankcases of a Norton 650 ss to a mirror finish, then a week later I read in a bike mag that it was the worst thing I could have done cooling wise. ( I wont tell you how long ago that was ) but it never overheated.

utopia · 30-03-2015, 11:15 PM

I'm sure that the heat transfer between the inlet tubes and their surroundings would be less for the polished tubes, but the question is.. are they losing heat to cold surroundings or gaining it from warm surroundings due to the heat from the engine combined with their position in a little nook between the cylinders where they may get less airflow.
My original statement implied that they were in a warmer environment, but I'm not at all sure that assumption is correct.
It fact, now that I think about it, it probably varies with speed. I guess they'd be heating at standstill though.
But, like you, I'd probably polish them anyway ....unless it was known to be detrimental.
I'm a sucker for the look of polished ally, but I also like its honesty and simplicity.

Mr Gazza · 31-03-2015, 10:43 AM

I wouldn't like to get involved in arguing whether it was good or bad for the inlet tract to be warm or cool, but.
Experience with Ajay and Matchless twins taught me that it is very undesireable for the heat to transfer to the carb(s). They would suffer terribly if no insulation was provided from the heat.
The original fitment was a "Paxolin" or "Bakerlite" gasket which went between carb and manifold...So the manifold was still allowed to get hot with no ill effect...And was frequently polished.

I would say that the Ducati set up with large rubber adapters to mount the carb to the tubes would provide ample heat insulation..........Polish away..

Capo · 31-03-2015, 01:38 PM

These days, it is considered detrimental to engine performance to polish inlet tracts.

Polishing inlet tracks would have an unmeasurable effect on heat transfer. Not considering the latent effect of the fuel vaporization. An elementary knowledge of thermodynamics would substantiate this.

It was never about temperature, rather an attempt reduce boundary friction, often as a result of port modification.

Ducati inlet tracts are produced on a 5 axis mill so they are all identical

Mr Gazza · 31-03-2015, 02:25 PM

Not sure if I am blinded by science or baffled by bullshine, but I did'nt understand a word of that, Capo..

I think you may have taken a swerve and moved the discussion to the inside of the tract rather than the outside.

Polishing the inside has been proven to be worse than a rough finish. the best being a dimpled surface like a golf ball apparently. at least that is what they found at ERM when I used to visit them in the early 90's...They did a lot of work on 7R and G50 heads...As indeed did the AMC race shop in the 50's and 60's....Williams is a name that springs to mind.

29-03-2015, 10:05 PM	#52
Dookbob Guest Posts: n/a	Just go on EBay and search for crankcase breather filter, measure the diameter of the breather stub first because they come in various sizes. Also, if you are still running with the air box you will need a rubber bung for the hole that the catch tank hose used to attach to. Last edited by Dookbob; 29-03-2015 at 10:11 PM.. Reason: Addition

30-03-2015, 02:44 AM	#55
gary tompkins 1/2 man - 1/2 pogo-stick Join Date: Aug 2002 Location: Dartford, Kent Bike: M900ie Posts: 7,241	I think 19mm is a common size for many of the breather outlets But it's a good idea to check it first http://www.ebay.co.uk/itm/19mm-Engin...item2edeff3107 __________________ GT Fully paid up member of the S.A.S. (Scottoiler Appreciation Society) 27,000 miles on original chain - and still going strong!

31-03-2015, 01:38 PM	#59
Capo You Are What You Is Join Date: May 2005 Location: A Foward Location Bike: S4r Posts: 1,948	These days, it is considered detrimental to engine performance to polish inlet tracts. Polishing inlet tracks would have an unmeasurable effect on heat transfer. Not considering the latent effect of the fuel vaporization. An elementary knowledge of thermodynamics would substantiate this. It was never about temperature, rather an attempt reduce boundary friction, often as a result of port modification. Ducati inlet tracts are produced on a 5 axis mill so they are all identical Last edited by Capo; 31-03-2015 at 01:43 PM..

25-03-2015, 02:30 AM	#46
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,562	I was just thinking today that, with that frame and engine colour, your most likely choices for the tank would be either red or white. In which case I was rather hoping that my old tank would become white, as I'm not a big fan of red. But the silver titanium option sounds perhaps even better. It matters not really, I suppose, but nevertheless I'm pleased. I thought the tank was decent inside. For information, since I've had it (which has been nearly always) its been kept largely empty over winter but, crucially in my opinion, in an UNHEATED shed with good ventilation. Its good to know that the strategy seems to have worked. Downside is I freeze my nuts off in there when that cold east winter wind blows ! My thoughts on the rose joints was not so much that there might be insufficient thread engagement but more that the end of the hoop was now effectively a lengthy bit of fairly thin threaded rod. Probably not a problem unless maybe the joint gets stiff, in which case it'd perhaps only hasten a failure that would happen anyway. But the stress-raising effect of the vee thread, over that extended length, it just kind of caught my eye.

25-03-2015, 10:56 AM	#49
Dookbob Guest Posts: n/a	I,m not a lover of Rose joint extenders to be honest, but these that I have fitted are the McGill version which have a longer threaded part than the originals anyway, which is what Utopia spotted ( as engineers do )

25-03-2015, 01:38 PM	#50
Nottsbiker Guest Posts: n/a	You ever up for visitors from across the border? My bikes ages away from the road but it would be great to stand around in a garage talking bike

29-03-2015, 10:32 PM	#53
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,562	I notice that you've put a nice polish on the inlet stubs. I'm very likely to do the same someday. Now, I realise that the difference it makes is miniscule but, just for interest's sake, what are your thoughts on whether the shiny surface is better for the carburation, or worse. My thoughts are that it may well be better, as the polished surface would absorb less engine heat than the original, slightly matt finish ( thus keeping the mixture cooler). If the shine makes it worse though, even by a tiny amount, then I probably wouldn't bother. Shiny is nice, but not at the expense of efficiency. That would be sacrilege really.

30-03-2015, 11:15 PM	#57
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,562	I'm sure that the heat transfer between the inlet tubes and their surroundings would be less for the polished tubes, but the question is.. are they losing heat to cold surroundings or gaining it from warm surroundings due to the heat from the engine combined with their position in a little nook between the cylinders where they may get less airflow. My original statement implied that they were in a warmer environment, but I'm not at all sure that assumption is correct. It fact, now that I think about it, it probably varies with speed. I guess they'd be heating at standstill though. But, like you, I'd probably polish them anyway ....unless it was known to be detrimental. I'm a sucker for the look of polished ally, but I also like its honesty and simplicity.

31-03-2015, 10:43 AM	#58
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,985	I wouldn't like to get involved in arguing whether it was good or bad for the inlet tract to be warm or cool, but. Experience with Ajay and Matchless twins taught me that it is very undesireable for the heat to transfer to the carb(s). They would suffer terribly if no insulation was provided from the heat. The original fitment was a "Paxolin" or "Bakerlite" gasket which went between carb and manifold...So the manifold was still allowed to get hot with no ill effect...And was frequently polished. I would say that the Ducati set up with large rubber adapters to mount the carb to the tubes would provide ample heat insulation..........Polish away..

31-03-2015, 02:25 PM	#60
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,985	Not sure if I am blinded by science or baffled by bullshine, but I did'nt understand a word of that, Capo.. I think you may have taken a swerve and moved the discussion to the inside of the tract rather than the outside. Polishing the inside has been proven to be worse than a rough finish. the best being a dimpled surface like a golf ball apparently. at least that is what they found at ERM when I used to visit them in the early 90's...They did a lot of work on 7R and G50 heads...As indeed did the AMC race shop in the 50's and 60's....Williams is a name that springs to mind.