Kiha physics question/s

[CaptainBazza]

I'm currently working on a railcar project using the Kiha physics as a starter. I have the vehicle running pretty much the way I want it to, with 4x speed gearbox (5x is not supported) when I found the infamous Kiha bug - in reverse it has only one speed - bloody fast.

Has anyone found a workaround for this bug, apart from driving in reverse, with the brakes partially set? Thanks in advance.

[ianmacmillan]

The gears are reversed too.

1st is 4th.

2nd is 3rd

etc

[ianm42]

The railcars that come with 'German Railroads 1' have 6 gears. Is it just 5 that is not supported? I will check how they behave in reverse.

[CaptainBazza]

Gears in reversed order? That's strange, because the RM I'm tuning had an official top speed of about 75mph, achieved through a 5x speed box, but using a 4x box I was able to reach 78mph in top gear on the NE Corridor flats, which would have been protypical.

Here are two of the relevant sections of the ENG:

GearBoxNumberOfGears( 4 )
GearBoxDirectDriveGear( 4 )
GearBoxMaxSpeedForGears( 15 27 41 78)
GearBoxMaxTractiveForceForGears( 25007N 20000N 16000 10500 )

and........

Gear( 0 2 1 0
NumNotches ( 5
Notch ( 0 0 Dummy )
Notch ( 1 0 Dummy )
Notch ( 2 0 Dummy )
Notch ( 3 0 Dummy )
Notch ( 4 0 Dummy )

The original Kiha 31 ENG has the max diesel level at 500 gallons, which I find remarkable because that's 14 hours duration at the stated consumption of 35 gals per hour.

The ENG I'm tweaking has max diesel level (and other fuel capacity) set at 70 gals, but the HUD is still showing 500 gals. I did a search of the ENG and found no reference to 500 gals, so from where is the HUD reading the fuel capacity figure?

"Curiouser and curiousier." said Alice, the railcar groupie.[/i]

[CaptainBazza]

That line should have read:

GearBoxMaxSpeedForGears( 15 27 41 78 )

[CaptainBazza]

For no apparent rhyme or reason ( in the true TS fashion) the HUD nowshows the correct fuel capacity. I refuse to bang my head against the nearest brick wall, I really do!

There appears to be no workaround (that I've found so far) for the 'reverse-at-full-speed-fiasco' bug. The only thing to do is to reverse the railcar at the end of its trip, via a wye, which defeats the purpose of having a railcar driveable from both ends!

[micksasse]

Don't think I can actually offer any help here, but I'm interested in what you say about gear ratios. In particular, I've noticed a slightly 'odd' thing about the class 101 dmu supplied with the Cambrian Coast route: from a standstill, you can actually start off in 4th gear if you want to! And if you do, not only will it not stall, but it will actually accelerate faster in 4th than going up through the gears!

Programming error or another MSTS quirk (hmm, somehow I suspect the latter!).

Cheers

[CaptainBazza]

That reminds me of a 'gear' story, from another time. My working career was spent in marine radio, as a NZPO coast radio station operator. At this time (mid sixties) we had transport supplied from town to the radio station, a distance of about 8.5 miles, in the form of Mr Ford's Dagenham Donkey (a rather flighty mini-van with seating for about 8 people).

On this particular occasion the Queen Mother had been visiting New Zealand and she was leaving the Port of Bluff on the 'Gothic'. Our mini-van was requisitioned as transport for a pack of journalists and we were given temporary use of the Chief Postmaster's big black Humber Super Snipe, the long bonnet, Commer straight 8 block engined, version.

The huge car weighted in at about 3.5 tons and the bonnet seemed a mile long to me, a newly qualified driver at the time. The damned monster was parked with the bonnet towards the concrete wall of a building. So typical of Brit cars, the gears were not marked on the gear knob, and this was at a time when each manufacturer had their own version of a gear shift layout. The gearstick seemed like a yard or two long and wobbled all over the place as I frantically tried to find reverse. I did, after about five minutes, 4.99 of those spent edging ever closer to that solid concrete wall as I found some forward gear instead of the elusive reverse. At the back of my mind was the thought that I didn't want to go down in NZPO history, as the very junior bloke who bent the CPO's pride and joy.

Finally, with great relief, I slipped it into reverse (a mere fluke) and moved back from the building and onto the next stage of Snipe versus Bazza, finding the gate to first gear. Well, to cut a long story short, I only found TOP gear, and proceeded for the rest of the 8.5 miles as if driving an automatic. The compression of that straight 8 big block truck engine must have been impressive! Did I mentioned trying to turn the .? This so called luxury car didn't have power steering, so it was a case of holding onto that huge steering wheel and forcing the vehicle around each corner and bend in the road.

I made it safely to work and even worked the 'Gothic' as she carried the QM away from Bluff and back to civilisation.

PS. I learned very quickly there were no powerboosted brakes fitted, either.

[matrix358]

I tried reversing a midland mainline class 170 yesterday, shot off like a rocket

[baldwin]

GearBoxMaxSpeedForGears( 15 27 41 78 )

Those speeds are the maxima for each gear, so 4th will give you 78 as opposed to a top speed of 75. At present I have run the Kiha with 6 gears in automatic mode, both hydraulic and mechanical.

It is possible to reduce the acceleration rate in reverse by adjusting this line GearBoxUpGearProportion( 0.85 ), downwards , but if you go too far it really affects the forward acceleration rate badly.


Edit for new info
Following on from the above, another post in this thread mentioned that the gears were backward in reverse, I dont think that is strictly true, but it led me to try out something. If you put the thing into reverse and then select first gear the engine revs up and away you go like the proverbial scalded cat. Not much use if you are running an automatic box and you will have to use the brakes to control the speed.

If you are using a manual 'box however, the scenario is much better. Start out in first to get it rolling, and then run up through the gears until you get one that suits.

I am currently using a 6 speed manual box on my test unit, here's the bit that gives you all six gears
Gear( 0 2 1 0
NumNotches ( 7
Notch ( 0 0 Dummy )
Notch ( 1 0 Dummy )
Notch ( 2 0 Dummy )
Notch ( 3 0 Dummy )
Notch ( 4 0 Dummy )
Notch ( 5 0 Dummy )
Notch ( 6 0 Dummy )

Not needed for an auto 'box though.

Mervyn

[CaptainBazza]

Thanks for the info. I did further extensive testing, as always, with variable results. These variables appear to be due, in part, to a very strange quirk of MSTS - when running the same consist, under the same operating conditions in successive sessions, it (the physics) appears to react differently. To make matters worse, the Kiha physics are thoroughly screwed in reverse running, and no amount of retuning and tweaking can fix what is really a hard coding problem.

I hope this bug has been fixed in MSTS2, otherwise a whole major class of rail vehicles will remain only partially functionable.

To achieve satisfactory terminal to terminal rail operations of Kiha type vehicles in TS1, run them terminal A - waypoint - to - waypoint - terminal B, by setting up an activity for A to B sector, and another activity ( with train reversed ) from B to A, for the return journey sector.