Another no-Monster build thread

[koko64]

  Thanks for the update.

[ducpainter]

I know a few people capable of shimming Duc lower ends.

I'm not one of them.

[MonsterHPD]

Hello, all.
It´s been a while again, so I suppose an update would be prudent, just in case anyone is still interested.

Starting with the gearbox, I somehow ended up with more parts than I needed, and did not really know what to do.Then I did quite a lot of suspension work for a friend who had a broken 848 motor. We struck a deal where I got the gearbox as a partial payment for the suspension work.
In the end, I used the standard HYM1100 shafts, and I think 1st and 2nd gear sets (I have it noted somewhere …) and the rest is 848 close ratio.
I´ve noted that if you just use a plier to spread the lock trings on the shafts, they actually deform and don´t sit as tight in the grooves as they might. I use some welding rod and other bits and pieces to ease the rings in place. A bit fiddly, but judging by the ring gaps, it works.

2017-11-28 13.19.50 by torbjörn bergström, on Flickr
    
Doing the shimming really is not that difficult, but you need to be systematic. First time around, I wasn´t, so I had to re-start the process. This time I started with the Ducati standard values (not so many shim thicknesses to chose from in the new motors), then adjusting to get everyhing as good as possible (i.e., equal dog engagement, shaft end play towards the lower tolerance, shift drum towards the upper tolerance).
Starting with one shaft (or the drum) at the time, then adjusting in whatever direction seems appropriate. In the end, and after lots of crankcase openings and closures, hopefully a good compromise can be found. In this case, shaft end float is 0.09 and 0.11 mm respectiverly, shift drum is 0.40mm, and crank pre-load is 0.20mm.

Next up was the crank. Since I have never really done a crank all the way myself, I had to do a lot of investigation before I knew (or had an idea, rather …) what to do, I´ve had the crank balanced with the Carillo rods and Pistal pistons, and in order to do the rod assembly properly, I decided Carillo probably knows what they´re doing and did as they recommends, using rod stretch for correct rod cap assembly.

Rod bearing clearance was next to decide, and varous Ducati mnuls give various values, from a bit over 0.02 mm up to slightly less than 0.07 mm. Consulting with a friend at Volvo engine design, I decided to go for generous clearance in order to get more oil through the bearing, thus having as much cooling effect as possible. In order to establish correct measurements, some tools had to be organized:

2019-01-31 17.12.30 by torbjörn bergström, on Flickr  

With the yellow-marked  Duc bearings, I got clearances of 0.55 mm and 0.60 mm respectively.
The rod bolts were tightened to 0.11 to 0.15 mm elongation with torque between 38 Nm and 41 Nm, as per Carillo recommendation.

2019-01-31 17.10.57 by torbjörn bergström, on Flickr

The cylinders measured up nice straight and round, and piston clearance came out as 0.55 / 0.60mm, and ring end gaps were small but within Ducati recommendations.

Using standard 0.4 mm gaskets both between cylinder and crankcase and between cylinder and head, squish came out as 1.2 mm. I would have liked something closer to 1.0 mm, but I did not need the hassle. Compression was on the high side for an air-cooled motor anyway, at 12.0:1, so getting slightly lazy these days I decided that would have to be good enough.
Valve pockets are pretty generous, so with custom-made pistons even more compression would be possible.

2019-04-10 Hor insug 1 by torbjörn bergström, on Flickr      

I pondered for a long time what to do with the cylinder heads, in the end I sent them to Biggelaar in Holland for some porting (stock valves). It does look nice, but on the other side not very extreme, so I´m not sure just how much good it does, but with the more agressive cams it should be positive.

2018-11-20 09.36.01 by torbjörn bergström, on Flickr

One of the guides was a bit worn, so they put a liner in it. Luckily I saw it looked a bit strange, turned out these guides are not suited to that kind of repair; the material left after boring out the guide is very thin and consequently not very strong. This one cracked and I had to have it renewed.

2019-03-03 18.58.07 by torbjörn bergström, on Flickr

Finally, the motor was complete, unobtainium DP cams (timed at 114° lobe centers to keep cylinder pressures slightly lower) and all. So far, I have run it for two track days, spending more attention to listening to the motor than trying to go fast.

Still, the motor is totally different, where the stock motor feels a bit slow, this one goes and does not get lazy at high revs.

I have now changed oil, and made a cranking pressure test. Vertical showed 14.2 bar, and the horizontal 13.0 bar. That´s more of a difference than I´d have liked, so I´ll keep an eye on that. The stock motor showed 10.5 / 10.0 respectively; I would have liked a similar difference on the new motor.
Well, so far, so good as far as the motor is concerned.

On the bike side, I´ve built a new rear subframe to get the angle of the seat down a bit. I felt it was too much arse-up before, and I think this is better.

2019-05-12 17.20.27 by torbjörn bergström, on Flickr

It´s also good to have attentive friends join you at the track ….

2019-05-29 14.17.33 by torbjörn bergström, on Flickr

[Speeddog]

I'm assuming you were already aware of the split-cage needle bearings in the transmission?
Nearly lost my mind when I saw them the first time.

Love your snapring install solution, consider it stolen.

Did you re-cut the valve seat after the new guide?
Perhaps that's the weak cylinder?

Doggo has a nice jacket!

[koko64]

Good work

Nice breather box too. So you Evo'ed the motor really

[MonsterHPD]

Yes, I was aware of those bearing strips. When I first encountered them, I asked a friend who´s been working for a Ducati dealer more than 10 years if I should put new ones in a gearbox I was working on, but he said he´d never had anyone (including their workshop) exchange one .... so I suppose they are OK.

No need to steal, the snap ring installation is free. It´s a bit fiddly, but here´s the reason I use it (new rings in both pictures):

Pliers only:

2017-11-18 11.37.11 by torbjörn bergström, on Flickr

"Slide" method:

20171128_132528 by torbjörn bergström, on Flickr

It may not make too much of a difference, but it feels better, and it´s what it looks like when Ducati factory has done it.

I first had a 1098 box off Ebay assembled, when I noticed that the dogs leading edges were pretty rounded-off:

2017-11-18 11.41.33 by torbjörn bergström, on Flickr

I suspect a quick-shifter has been at work here .... the 848 box I now have has no such signs, and had never had a quick-shifter fitted.

The new valve guide was installed by a very experienced Ducati mechanic, who also told me to bring the valve since the seat has to be re-cut. Pretty obvious when you know it, which I didn´t . I try to make notes of "everything", but  can´t find any note of which head it was, and I don´t remember .... suppose my age is catching up with me.   

I suppose I have more or less Evo´ed the motor, and hopefully slightly more .... I´m told the Evo cams are somewhere in the middle between stock and DP.

Incidentally; I don´t like to start a new engine without having oil pressure first. After quite a while on the starter I still had no pressure. I took out the oil pressure sensor nd forced oil down the bore (into the oil pump) with a pump-type oil can. Oil pressure arrived quite quickly after that. Same phenomenon appeared after the oil change, so I did the same .... just feel better that way :-)   

Next part-project: Several years ago I bought a second-hand Innovate LM2 exhaust analyzer which I´m trying to bring to life before the next track day. Let´s see how that goes.

[Speeddog]

As long as the shaft and gear surfaces are nice, IMO yes, leave 'em be.
If any of the 3 looks scruffy, the whole set is scrap.

Those snaprings are broadly uncooperative.
I'm sure the factory has the same sort of tool concept.

On all snaprings that I install, I've taken to grinding a bit of an angle to the ends so they aren't trying so hard to slide off the pliers.


Those dogs and slots are hammered.

Hmm, if they had the valve while doing the guide, and cut the seat, it should be fine.
A leakdown check would help determine the guilty part(y).

If it's a fresh build, or a motor sitting dry for a while, the pumps don't prime well.
I've backfilled through the oil cooler delivery line, and turned the engine backwards so the pump fills it's supply gallery.

[MonsterHPD]

As long as the shaft and gear surfaces are nice, IMO yes, leave 'em be.
If any of the 3 looks scruffy, the whole set is scrap.

Those snaprings are broadly uncooperative.
I'm sure the factory has the same sort of tool concept.

On all snaprings that I install, I've taken to grinding a bit of an angle to the ends so they aren't trying so hard to slide off the pliers.


Those dogs and slots are hammered.

Hmm, if they had the valve while doing the guide, and cut the seat, it should be fine.
A leakdown check would help determine the guilty part(y).

If it's a fresh build, or a motor sitting dry for a while, the pumps don't prime well.
I've backfilled through the oil cooler delivery line, and turned the engine backwards so the pump fills it's supply gallery.

It´s a bit strange, I´ve read about leak down testers mostly in american magazines, and I have a description from a Practical Sportsbike mag on how to build one. However, I´ve never seen one over here, and I don´t know anyone who has one or has used one. Maybe now is the time to look up that Practical Sportsbike description ... 
In your experience, it´s a useful tool?

I´ll try your pump priming method sometime, it may be more effective than  just pushing oil backwards into the pump.

[Speeddog]

I had no idea it was a "local thing".
More than happy to help start a trend! 

Mine is a Yother brand, bought it ~early 90's.
No idea if it's notably better than any other brand, a good friend had one and said it was really nice so I went with it.
It's not much more than a particular selection of off-the-shelf parts, so making your own is pretty straightforward.

Mine looks largely the same as their current offering, other than mine has liquid filled gauges.
https://yother.com/collections/tools/products/yother-dual-gauge-leakdown-tester



Referencing the pic:
Air supply comes in from the left into the pressure regulator, there's no quick-disconnect coupling on the one in the pic, it's a "fit your own to match your air hose" deal.
There's ~4 common kinds of QD used here.

A safety suggestion from my FHE in using this tool.
Select a hose quick disconnect pair (end of hose and right side of the tool) that is *different* from your shop air hose.
I used mine frequently when I was racing, and as racing goes, the operator can be very very sleep-deprived.
Under those conditions, it's easy to lose focus and directly connect shop air to the cylinder without the tester in between.
That is a nasty surprise at best, the engine *will* try to turn quite forcefully.
That can increase the scope of repairs or cause a leak/defect in shop staff.

The pressure regulator is a relieving style, so you can adjust the pressure both up and down.
http://wilkersoncorp.com/faq_frl4.shtml

Ideally, you can select two gauges that read exactly the same, but it's not mandatory.
Just makes it easier to use in a sleep-deprived state.
Mine differ by ~3psi, I just have to account for that when reading them in use.


The black 'brick' in between the gauges has a small orifice, I've no idea of the actual size.
Essentially it allows comparing the 'leak' of the orifice to the 'leak' of the engine.

The usual method requires over 100 psi of shop air, such that the regulator can be set to supply 100 psi.
Then one merely reads the gauge on the right, if it's 97psi then the engine has 3% leakdown.
Can be used effectively at 50psi, just have to double the pressure difference to get the leakdown %.

[MonsterHPD]

Thanks for the info.

They are available over here as well, but in "my circles" have not been a cmmon diagnostic tool.

I´ll get one, however, and pay some extra by buying in Sweden so i can have emtric units a well. Helps when used in sleep-deprived circumstances :-)   

[koko64]

 

[MonsterHPD]

Hi again.

I got the leak-down tester today, real quick delivery. I did some googling before Iordered,and settled for one made by OTC Tools which acc to the net is an american company. However, when I opened it and read the info inside, there was the dreaded "made in China" in small print .... hope it will work properly. By buying locally, and from a known tuning outfit, I hoped to avoid China-made, but that´s how it is.

Anyway, I´m off for a qouple of days of track riding, and will try the leak-down test when I get back (assuming we´re all in one piece ...). I do have a couple of questions form the beginner to the experienced user:

1) The instructions say I should run the motor warm, then remove spark plugs etc and do the testing. However, I assume that in order to hear any potential valve leakage I´d need to remove  headers and air filters in order to hear anything, which would mean a cold test. Is that an issue, or what do you recommend?  

2) Should I use something to enhance whatever sound there might be, like a stetoscope or similiar?

3) I´ve always wondered how it will work with maybe 5 or 6 bar pressure in the cylinder. Won´t that want to turn the crank, even if I manage to hit TDC exactly?

4) Any other useful hints will be muc appreciated.

Kind regards,

  

[Speeddog]

Yah, difficult to avoid root sources sometimes.

1) I suppose using it on a warm motor will give a more consistent reading, as everything's oiled up and thermal effect on valve clearances and such more closely mimic running conditions.
    I think Howie can give realistic feedback on that.
    I've always done it cold.
    You can listen at the end of the exhaust, listen to the intake on the airbox, and listen at the oil fill hole. No need to remove anything besides the oil fill cap.

2) A stethoscope would be useful if any of the above 'ports' are difficult to access with your ear.
    And if you test hot, less likely to burn your ear. 

3) Even with 1 bar it will turn the crank if it's not real close to TDC and not restrained.
    I enlist a volunteer to slowly ramp up the pressure while I hold the motor at TDC with a 1/2" breaker bar and socket on the ringnut on the layshaft.
    At low pressure, I rock the crank back and forth a bit to find TDC, once found, I have the assistant then turn it up higher.   
    I don't use the standard crank turning tool, as they're easily ruined that way.

4)  This is sort of the standard fundamentally unsafe activity that's often done in a shop.
     Make absolutely sure the regulator is set to zero before attaching it to the motor.
     On an 1100 with the crank at ~90 degrees off TDC and at 7 bar, it's near 300 ft-lb at the layshaft.
     Sooooo, just keep it near TDC and it's fine.
     You can test by yourself with the crank at BDC. That does not test for ring/bore seal at TDC, so it's not the best.

[MonsterHPD]

Thanks :-)

[Speeddog]

Happy to help!