I have recently purchased a Bachmann spectrum 2-8-0 to use on my dc layout. I know it says that it has a flywheel, but it runs like it dosen’t. It seems to start like my older steamer without a flywheel. Do steam engines just run differently then a diesel? My old athearn diesels start up nice and smooth with flywheels. I have run the new engine for about an hour total. Do I just need to break it in a little more? Sorry for the newbie question. Any wisdom on this question would be greatly appreciated. Thanks
The Bachmann Spectrum’s 2-8-0 flywheel is too small to have any noticable effect. Most steamers with flywheels also have very little effect.
Thanks for the repy. I guess that’s a reason to use dcc instead of dc.
A flywheel has very little to do with how an engine starts. It is mostly used to help in “coast” over bad spots in the track where electrical pickup may be a problem. The momentum of the spinning flywheel is supposed to keep the motor turning if it cuts out due to electrical problems.
I was under the impression that flywheels were to help with not having “train set” start ups. I guess you learn something new every day.
What type of DC controller are you using? IIRC that has more to do with eliminating jack rabbit starts.(along with motor quality)
I have 2 Bachman B 23’s. One has large flywheels and the other has tiny ones. (same motors) There’s a big difference between how they run and stop, but not how they start up.
It’s an oldie but a goodie. An mrc 501 , I think. It’s old that’s all I know! The engine just seems to take more juice to get going. It goes nice and slow in pulse mode though.
I find that my locos will stop on a dime if they run out of power for more than half a second or so. This happens virtually never, but I have had occasion to see my BLI steamers stop dead, and with a slight nudge come back to life and accelerate prototypically all over again. Maybe if they all had 1kg of rotating mass it would make a big difference, but I don’t see that the flywheels add much to the operation of them. But, yes, I certainly agree that they should do very little on start-up. The idea is that they are meant to help propel the loco over the “bad spot” once underway with a bit of speed.
I really appreciate everybody’s answers to my newbie questions. It’s probably the controller I’m using. I just thought if my twenty year old coffee grinders started so well, the bachmann would too. I guess I can’t ask for too much with the old controller and brass track. Yes yes I know, brass track is bad! Thanks again.
I think the older motors take more juice to get them going. The newer ones don’t. This could account for the difference. It might just need a break in period too. When you run it slow, does it run smoothly or does it tend to jerk a little?
It seems to run fine once it’s going. Don’t get me wrong, it doesn’t jack rabbit start. It just doesn’t seem as smooth as I thought it would be. Maybe I need to clean my track. I suppose it’s possible that the bachmann is geared a lot differently than the athearns. That would make sense.
Remember that it is a COG drive, so it starts with little jerks…hence the downside of the Bachmann Spectrum line of steamers…but everything else is great.
David B
Indeed thats the theory.Thats why we have smooth running locomotives.
Take a locomotive without a flywheel and you have a “zip” start.Even a small flywheel helps.
I suspect the quick start might be due to the drive belt the 2-8-0 has.
I was a little confused when I bought it. It said belt drive and fly wheel. I thought that sounded a little different. I believe David called it a cog drive? Oh well, I like the engine, I was just concerned that something was wrong. I figure I’ll beat it into submission(break it in better)! Thanks everybody for the information.
I’ve experiance with a German engine (BR92 from Trix) that has fly wheel and belt transmission.
The belt transmission completly offsets the effect of the fly wheel. The belt need too much tension to work to give the fly wheel a chance to turn the mechanics.
Only a good DCC decoder can make the engine apear smooth.
ps. I have two Spectrum 2-8-0 on order. I wonder if is was a good choice… we’ll see:-)
As noted, small flywheels do more for the sales brochure than for jackrabbit starts. If an engine will not start smoothly because the motor and/or drivetrain is at fault, DCC isn’t going to do squat for it. All DCC does is control where the motor gets the DC voltange from; directly from the rails vs. from a DCC controller. You said that it starts smoothly in pulse mode, so what’s the problem? Why not use pulse mode? That is what pulse mode is there for. It will probably smooth up a little with more break in. Start in pulse and then switch over.
The belt drive does not have huge tension on it. It is a miniature timing belt (i.e., it has teeth on the belt) so it doesn’t rely on tension to maintain engagement.
If you are sure you are never going to use DCC in the future, open the tender, rip out all the electronic junk, throw it away and re-wire the tender trucks to the motor. This will lower your starting voltage by 3 volts and eliminate about 95% of the problems associated with Bachmann engines. While you have the loco and tender apart, file the little latching lugs off the male connector plugs, and NEVER seperate the plugs by pulling the wires.
I think I’ll just deal with it for now. I like the scenery more than operations anyway. This is my first layout since I was twelve. Now seventeen years late, here I am “playing with trains.” I bought the engine thnking some day I may switch to dcc. That would probably come with the next layout though. Thanks again to everybody who shared their wisdom with me!
Thats your problem, get a newer pack or it will give you will continue to have problems, I like my 2500’s from mrc, still inexpencive like 15 to 20 bucks on the right ebay auction but work almost as well as the newer ones. The 501’s had a taper whond (spell cheak please) reostate and the one i mentionted as well as others from that time period are mostly electronic as I understand it, anyway I got three and they all work great
Incase you don’t have the original diagram of the engine, here’s a link to one showing how the whole cogged belt drive is built.[:D]
http://hoseeker.net/assemblyexplosionbachmann/bachmannspectra4-8-0.jpg
