Poor Acceleration and Top Speeds - Locos

pfx

Well-known member
I've encountered a puzzling issue which so far, I've been unable to resolve.

I'm using TS12 without SP1. When using locos with a rake of carriages (6-8 carriages) I'm getting horrendous acceleration and top speed. It's taking miles to reach 50-60 mph. Typically the speed rises in two mph increments so from start, I get 1,2....no acceleration 3,4....no acceleration 5,6mph... and so on. This is a fairly recent issue and doesn't affect DMUs or EMUs.

I've tried an EDR, deleting and reinstalling the locos, cloning routes, all to no avail and it's getting to the point of me booting Trainz into touch.

Does anyone have any idea what the issue is and how I can fix it?

Any help is gratefully appreciated.

Cheers,
PFX
 
If your using at least two locos make sure that the engine spec kuids are the same. Locos made by two different creators will probably have different engines and thus will be working against each other. Had that happen to me on several occasions and finally went into the config files and changed the engines kuid to match all the same type locos. All my SD40-2 have the same engine kuid as do all the B40-2's Dash9's and etc. Hope this helps.
 
Drive manually...? :hehe::hehe:

Seriously the only thing I can think of, is could the AI be looking ahead to a speed restriction or adverse signal/junction? If anything I had the opposite issue (in TS12 49922) when using AI control to prove a route the train leaping from 0 - 20 mph in about 0.5sec, but if the next speed limit was within about 400 metres of regaining a higher speed it would only accelerate to around 1 mph more than the next lower limit.
 
Hi

You don't say if this is happening when driving the loco or if it is occurring with AI traffic. If it's the latter then it sounds similar to the problems that older locos have when used in TC3 or higher.

In the engine spec have a look at the max-accel and max-decel tags. In pre TC3 these tended to be quite low (about 2500 to 4000) which worked fine in the earlier versions of trainz. From TC3 onwards these tags needed to be much higher (typically about 4.5 times higher). For modern stock I often go higher still to get the acceleration rate that I need.

I never drive a train myself so if it is occurring in driver mode I have no idea I'm afraid. If it is in AI mode then perhaps you could post the name and kuid of one of the locos involved?

Regards

Brian
 
Apologies for omitting some important info. I'm getting this issue when driving myself. This is happening with all the locos I've tried, with the exception of the Class 91 and HST sets.

I don't think it is an issue with the locos themselves but possibly a local issue on my PC as this has only happened in the last 2 months. Prior to that point, everything was working fine.

I'm starting to think I may need to open a ticket for this one?
 
It might be against your usual traction ideas, download a couple of locos from jointed rail. Don't forget the dependancies etc. See how they run.
If they run badly it's a local issue you have.
If they run ok it's maybe old e-specs.
 
I'll try a JR loco but I'm already near certain I can rule out old e-specs as at least one is so new, it hasn't even hit the DLS yet.

There aren't any rules that would possibly cause this?
 
As was mentioned before mixing locos with mixed e-specs results in the lower ruling. For eg a 9f and a 3f. Looks good but pulls like 2 3f's.
 
I'm not mixing locos. Where I've been using them in mutliple, it's been multiple of the same loco type. I've also tried them singly.

Another symptom is when engage notch 1, the loco pulls off then slows to a speed that won't even register as 1mph. I can go right to notch 8 and get no wheel slip.

Out of interest, I tried decoupling the consist while accelerating. On a number of ocassions, this has resulted in a brief decouple then recouple with two knuckles then displaying where there should only be one. When the loco has decoupled, acceleration appears normal. It is only with a consists attached that this problem persists. I have tried various rolling stock, all with the same result.
 
Hi

As was mentioned before mixing locos with mixed e-specs results in the lower ruling. For eg a 9f and a 3f. Looks good but pulls like 2 3f's.

With AI trains the problem is caused by the way trainz calculates the maximum speed of two or more locos that are coupled together and is down to different max-speeds in the e-spec. It calculates the combined speed by dividing the lowest max-speed by the highest and multiplying the result by the line speed.

To see an example of this, have a look at the built in (in TS12) class 105 DMU where the two units use different e-specs for some reason. The two units coupled together will only run at about 75% speed. In King's Cross station, where the speed limit is 8mph, these units will only run at 6mph which is clearly ridiculous. The solution is quite simple, either use the same e-spec in each unit or make sure that the max-speeds in each e-spec are the same.

Regards

Brian
 
As pfx has stated it's happening with single loco's, it's got to be some other problem, might be worth looking at jetlog.txt which may give an indication of a problem, or look and see if any rules used have recently been updated, could be a simple case of remove the rule, save then add it back.
 
This might sound crazy, but has anything changed with the rake of coaches? There are specs for those as well and perhaps something was updated, such as max speed, weight, etc. that may prevent the consist from moving at the speed you are supposed to operate at.

John
 
Thanks for the continued suggestions folks.

Malc, I'll try removing all the rules though the ones in the session are the standard rules I think are set as default.

John, I've tried various rakes of coaches and wagons. Same story no matter what I try it with.

Some locos are marginally better than others. I just don't get why this is specific to loco hualed and not multiple unit stock.
 
I have had a similar-ish sounding problem before - jerky unresponsive motion when accelerating. I think this was beacuse my PC wasn't seeing all the memory I had available, and was running on only one core. A clean out of dust and everything was fine again. I've also have a process called WDFME.exe which persistently keeps hogging 50% of the CPU in the background, that I have to keep killing off. Maybe worth checking nothing similar is happening on your PC?
 
Cheers.

As everything but locos are running fine, I think that may be unlikely. The motion isn't jerky at all, FPS remains smooth and high, so not a PC issue I'd guess. When I say the acceleration is jerky, I mean I'll get normal acceleration in 2mph increments, no acceleration (though the loco continues to travel smoothly) then another 2mph after 3 seconds or so, no acceleration and so on.
 
@Malc, I'll try a defrag and see if that bears fruit. Cheers.

@stovepipe, no sign of that process running.
 
I'm using a load of locos but this is one of the epecs. CIE Class 141 960hp EMD 567CR enginespec,<kuid:368699:50141>

I've been trying US, UK and Irish locos and have discovered US locos are having no issue hauling a rake of 5 Mk3 carriages.

N3V helpdesk have advised me they are unable to help as the locos with the issues are not built in. They must have just decided to stop working to annoy me.
 
Just had a peek at this in cm, don't know if you've seen it.

CIE class 141 Enginespec, as fitted to B141-177. Power 960hp, TE 37500lbf, maximum speed 76mph. Correct loco mass 67060 kgs.

For best performance in CAB mode use with rolling stock fitted with my coach and wagon enginespecs.
 
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