Page 1 of 2

Dr800 starting issue

PostPosted: Fri Aug 10, 2018 8:01 pm
by Nick65
Help and advice please. Dr800 1990.
Starting from cold, ignition on, decomp lever pulled in and released. Bike fires straight up without choke on the press of the starter. Ticks over and rides perfectly.

Then... when you stop engine and try to start again, decomp lever of course, it's as if the battery has no charge. Starter very sluggish and not even enough power to get a revolution out of engine. After a couple of tries, the starter stops and the solenoid clicks. I did manage to bump start it to get home and it ran perfectly. Once I got home I kept the engine running and check the charge which was over 14.2v and with the engine off, 12.8v.

I've read here that this could be either worn brushes in the starter or worse, the starter clutch (or of course the battery itself).

If anyone has experienced similar issues can you let me know what's the most likely cause.

Re: Dr800 starting issue

PostPosted: Sat Aug 11, 2018 7:51 am
by BigBob
Could be several things really.
Check your battery terminal connections are tight.
Battery. They don`t tend to last too long on Bigs for some reason, so if it`s more than a couple of years old replace it with a Motobatt.
Try connecting up another battery to yours and see if it fires up no problem.
If it does then the problem lies with the solenoid or the starter itself.
Solenoids do die eventually, and connections to them get cruddy so check by jumping a screwdriver across the terminals to see if she fires up.
Starter motors don`t have brushes issues as far as I`m aware but have been known to fry themselves but the above check will show that up.
It`s unlikely, but your secondary starter cogs could be damaged and jamming.
If your starter clutch is cream crackered then the starter will just spin over and not engage the crank, so it`s not that.
Try electrics first as they are usually at fault and most of the time it`s a bad earth.
Report back with your findings

Re: Dr800 starting issue

PostPosted: Sat Aug 11, 2018 8:54 am
by Nick65
Thanks for the advice bob, I'll check everything out and keep you posted. Just to say, when you press the starter button and the starter begins to turn, on first start up it fires in a fraction of a second but it feels like if it didn't catch straight away there's not enough power to even turn the engine for even one revolution let alone cranking it.

When it doesnt fire, you can definitely hear the starter turning engine, then the starter changes tone like it is spinning as you describe but not turning engine over and then eventually the solenoid clicks. I'll keep you posted.

Re: Dr800 starting issue

PostPosted: Sat Aug 11, 2018 7:01 pm
by wundis
Don't trust the 12.8 volts on the idle battery.

I had an experience with the BIG when a yuasa (worst overpriced shit nowadays) battery was showing good voltage, but had failed cells inside = the CCA went down dramatically.

Re: Dr800 starting issue

PostPosted: Sat Aug 11, 2018 8:05 pm
by Nick65
Thanks wundis. I thought that might be the case, amps rather than volts for cranking power. I'm going to do the checks that bob suggested and if that all turns out all right I'll focus on the battery itself. It's a generic Chinese brand so probably crap when new.

Re: Dr800 starting issue

PostPosted: Sun Aug 12, 2018 7:39 am
by wundis
Also, keep in mind, cheap chinese shit-start cables won't put through 200 amps :crazy:

Re: Dr800 starting issue

PostPosted: Sun Aug 19, 2018 10:41 pm
by Nick65
Here's the latest update.
The bike starts with a jump and cranks over nice and healthy so the original battery seems to be the likely culprit.

I opted for a new Motobatt AGM. The standard fitment for this bike has a maximum cca of 210amps. I checked if it were possible to get a higher cca to help with starting but found that the battery would be simply too big and not fit into the battery box.

The larger 151mm battery with a CCA of 250 would fit between frame rails but the battery box would need to be heavily modified. I tackled this today and it all fits nice and snug. Here's what I did.
1. Cut and increase width of battery box by 15mm.
2. Cut off the right hand side top mount and discard.
3. Fabricate new top mount so it runs on the outside of frame rail. This mount is bolted on rather than welded so it allows easy removal of battery in the future.
4. The right lower bracket which bolts to the air box repositioned to left by 15mm.

The battery box was essentially increased in with by 15mm to the right so all the mounting points on left hand side remained unchanged. The rectifier, CDI, solenoid, flasher relay and a black box of unknown function all mounted in their original positions.

All buttoned back up in an afternoon. Really pleased with the results. I think the battery is the MBTX16U and only cost about £10 more than the standard one.

I have pictures of the mod but haven't sussed out how I can attached from my Gallery.

Happy riding.

Re: Dr800 starting issue

PostPosted: Mon Aug 20, 2018 9:06 pm
by Nick65

Re: Dr800 starting issue

PostPosted: Mon Aug 20, 2018 9:09 pm
by Nick65
Just wanted to add, it's still to be powder coated but at the moment I'm just going to ride it and have fun.

Re: Dr800 starting issue

PostPosted: Tue Aug 21, 2018 8:06 am
by BigBob
I`ve got the stock Motobatt battery on all my Bigs and they all kick out more than enough power to spin the engine over nicely, so you should have no trouble, even in winter.