Another no-Monster build thread

[MonsterHPD]

Well,
numbers are fun, passing someone is more fun :-)

Anyway, I´ve had some input from members on the german forum, where 2V projects like this one are more common than here. It indicates that the inlet ports, even when "conventionally" ported, are limiting power at high revs. This also makes me wonder if this is the reason that max power revs are so similiar at the M900 test, regardless of header length.

So, as a long-term project, I´ll look at doing a pair of down-draft heads. Long-term .... 

[MonsterHPD]

Hello, everyone.

Winter over here (more like constantly bad weather), so time to attend to some projects.

I´ll see if I can get the ST2 cams installed in the M800 with standard pistons, and when the heads are off, I´ll do some porting as well (for better or worse ...) and decided I needed a work station, so this is my prototype (height adjustment and vacuum connection still pending):

20191207_171734 by torbjörn bergström, on Flickr

With the M800 motor on the engine stand, I will take the opportunity to test the leak down tester, so all the tips I got earlier are very much appreciated now.

Kind regards,
Torbjörn.       

[koko64]

 

Who is helping you with the porting?

[MonsterHPD]

Well,
I have some plans to do it myself. If that will be a help or not, remains to be seen .....

I will do some testing with welding and cutting on this cylinderhead, which is ruined anyway, and take it from there.

First actual work will be on the M800 heads (depending on what I learn as described above), and a bit further down the road (if I do not screw up big time) will be a set of down-draft(ish) heads for the HYM1100 motor.  If that could help to maintan the torque for another 500 rpm or so, power would benefit quite substantially.

So, it will be a process of doing, (hopefully) learning, and finally getting some useful hardware.

As someone cynically put it, any tuning can be considered a success as long as you do not lose more than 25% of what you started with .... I hope to better that, at least :-)     

[koko64]

 

You trying DP or Evo cams? Maybe Kaemna 47mm inlet valves?

[MonsterHPD]

It'sa,bit of a long-term project (aren't they all ....), the m800 heads beeing this winters project.
The HYM heads would be for the track day bike, so hc pistons and dp cams. No big valves, at least not first time around. Time will tell :-)

[MonsterHPD]

Hello, all.

The track bike has been in a corner of the garage for the winter, no specific plans for changes for the coming summer. However, after some discussions on the german Ducati forum, I´ve realized I´m relly prety tight on piston ring end gaps .... I just checked what was stated in the HYM1100 workshop manual (0.2 to 0.6 mm), with 0.25 or so mm I did notthink any more about it. It is, however, quite tight, something like 0.4 would be more appropriate. So far, it seems nothing´s gone wrong, but I would like to correct this.

In order to make the work more orthwhile, I´ll try to correct the squish clearance, now at 1.2 mm. I might get away withjustremoving the 0.4 mm base gasket, but I don´t want that much compression, so a compromise would be 0.2 mm base gasket, which do not exist.

However, a few hours with a base gasket, some mm paper and CAD, I had 2 steel templates cut with high pressure water jet. hopefully, 0.2 mm sheet brass base gaskts will do the trick, and give me a 1.0 mm squish. I just have to find the time to do the job .....
 
20200222_195855 by torbjörn bergström, on Flickr 

         

[Duck-Stew]

Nice job there!!

[ducpainter]

I wouldn't adjust the ring end gap. If you have adequate gap, you have adequate gap. It will get larger as the rings wear.

Be very careful with squish. I lost a motor from one being built too tight. 1.0 mm is minimum.

[koko64]

The HYM heads would be for the track day bike, so hc pistons and dp cams. No big valves, at least not first time around. Time will tell :-)

Depending on the nature of the tracks you visit, have you considered Kamna Sport cams Vs DP cams? Are the tracks tight or with long straights?
nockenvergl by Tony Kokonis, on Flickr

[koko64]

Well,
numbers are fun, passing someone is more fun :-)

Anyway, I´ve had some input from members on the german forum, where 2V projects like this one are more common than here. It indicates that the inlet ports, even when "conventionally" ported, are limiting power at high revs. This also makes me wonder if this is the reason that max power revs are so similiar at the M900 test, regardless of header length.

So, as a long-term project, I´ll look at doing a pair of down-draft heads. Long-term .... 

I guess very high quality (expensive) conrods are required for more rpm with a 71.5mm long stroke motor. Also, regarding high rpm power, even the Evo cams are milder than 900V cams, so is there an issue with controlling the mass of the large valves, or is the issue valve to valve clearance? Are Ti valves being used with the 47mm size?
What do Kamna think about this?

[MonsterHPD]

I wouldn't adjust the ring end gap. If you have adequate gap, you have adequate gap. It will get larger as the rings wear.

Be very careful with squish. I lost a motor from one being built too tight. 1.0 mm is minimum.

Yeah, I know, and I´m not panicking over the end gaps, but I´d like some more margin should the motor run very hot for some reason.
For squish, I´m aiming at 1.0 mm, I don´t bother to test the limits .... my pal once built one with 0.7 mm as part of a later-defunct E85 project. It broke down for other reasons, but you could see the piston classification "A" in the soot in the head, suppose that was as close as it gets.   

[MonsterHPD]

Depending on the nature of the tracks you visit, have you considered Kamna Sport cams Vs DP cams? Are the tracks tight or with long straights?
nockenvergl by Tony Kokonis, on Flickr

I have not considered other cams than the DP cams, basically because I have them, and I´m exploring other venues to useable power. A frien here is building a motor with Kämna cams, don´t know anything about them now except that they have lots of lift (13.something mm), which I do not think will help power unless you have really good porting. If his motor turns out very good, maybe I´l reconsider eventually.

Our tracks are (with one exception) short with short straights, and the long one has a problem with neighbours surprised by the noice from the track they moved close to ...     

[MonsterHPD]

I guess very high quality (expensive) conrods are required for more rpm with a 71.5mm long stroke motor. Also, regarding high rpm power, even the Evo cams are milder than 900V cams, so is there an issue with controlling the mass of the large valves, or is the issue valve to valve clearance? Are Ti valves being used with the 47mm size?
What do Kamna think about this?

Well, I suppose Carillos or similar gives some peace of mind, at least. I was also slightly surprised by the very nice running caracteristcs of the motor with some lighter rods and balanced crank/ rods/pistons assy. 

With big valves, valve-to-valve clearance will certainly be an issue, presumably timing vs. lift will always be a compromise in the overlap phase.
I suppose Ti valves are available, but have not investigated since I´ll stick with stock valves until I see a real need for something larger. I suppose I´d be too old to do something about it by then anyway .... 

[koko64]

Its good having the Germans so close to consult, they are doing great parts and making good power with 2 valve motors.