SaRo 163 and 165 - what's the difference?

[Welshbloke]

While looking at the Kato diagrams for the 153 Series I noticed that they have two SaRo types listed, the 163 and 165. Why the difference? I know the 153 and 165 Series swapped SaRo and SaHa trailers between sets, but where did 163 come from? The two look identical in model form!

[bikkuri bahn]

The saro 163 are orphan units, the only examples of the cancelled 163 series emu design, which were basically 153 series units with upgraded traction packages (mt46 replaced with mt54 motors), intended for routes in warmer (i.e. coastal) regions with gentle gradients.  JNR decided to stick with the 165 series as the new standard, which had more "bells and whistles", rather than produce a separate series which would have required a different maintenance regimen (and thus additional costs). Also, the 163 series would have less route availability, such as for seasonal work to ski resorts, and (interestingly) to summer beach services on the Boso Peninsula- the latter requiring fast start and stops to thread through the 101 series local service pathings on the Sobu Main Line.  The cs12 throttles on the 153/163 series couldn't handle/initiate the rapid acceleration required on congested urban routes.

[Welshbloke]

Ahh, thanks, that explains it!

 

Still hunting for a Kato 153 Series set to go with my MoHa 152/153. Have spotted an old one but auction doesn't end for a few days, so will see what happens.

[marknewton]

Yes bb, thanks from me as well. I also was curious about that.

 

Cheers,

 

Mark.

[velotrain]

I have to wonder why JNR didn't come to that conclusion before they initiated the 163 series.

 

It sounds like they have orphan units which require a different maintenance regimen.

[kvp]

They probably ordered the 163 series trailers before realizing the 165 series would be better for both jobs. This is similar how the JR East 235 series got its platform door compatibility trailers. They were made for the 231 series, but then the 231 series got retired from the line and scaled back to 10 cars. This left the relatively new 231 series trailers (SaHa E231-4600) without sets, so they got added to the 235 series as SaHa E235-4600 cars. But they don't even look like 235 series cars, so you can spot them by looking at the roofline (and of course the door/window alignement). This shows that ongoing projects may have revisions, where the order is changed while being built. The difference between the 163 and the 165 series is minor and only concerns the brakes being able to operate in snowy conditions. JNR decided to get the better sets only, but for some reason (probably cost), they kept the already built trailers without rebuilding and renumbering them into 165 series trailers. And on top of this, being trailers, they could run with the 153 series too without any modifications.

[Welshbloke]

Having just unwrapped a Kato 153 Series (very old but in good condition) I notice that the SaRo 153 looks identical too (and the SaRo 455). Evidently JNR got their money's worth from the bodyshell tooling! The SaHaShi 153/165/455 appear to have identical bodies too.

 

The set is the old six car "NTrain" one formed KuHa-SaRo-SaHaShi-MoHa-MoHa-KuHa. Luckily I have a dummy MoHa pair to slot in and make a more realistic eight car set.