Mofo's 690 Duke

[bevvo]

What is the issue with the rocker arms?

I had a 640 duke a few years ago with rocker arm issues - it was due to insufficient oil on the bearing, if I recall, so they needed replacing at reqular intervals.

[Taipan]

KTM know about the issue and modded the later ones but typically didn't recall the old ones

I've read that but asked at 2 different KTM dealers and they claim there is no updated part....which actually sucks more than having one but not doing a recall, as means that the new ones are just as likely to fail I guess.

When I asked at Jim Aims last time the bloke said it wasn't worth replacing mine if they were fine as the new one's might not be better The bloke this time was of the opinion it's not a bad idea to change as typically they go as they wear so better to have new ones than take the chance.

IMO it's a no brainer to get the arms replaced whilst they're in there.

Yes that's my thinking. I'm paying them to do the valves I might as well get them to do the rockers whilst they are in there. And in spite of the above I think it's probably worth doing as mine have done 12k now so hopefully new ones will be better.

Hmmm, i'm sure the service guy told me the new ones are different? Something about different design and end float springs to mind, but I could have it arse upwards and I'd willingly concede a dealer should know better than me. That said, if the replacement ones are no different, why do they agree with replacing them as a precaution?

[Supermofo]

KTM know about the issue and modded the later ones but typically didn't recall the old ones

I've read that but asked at 2 different KTM dealers and they claim there is no updated part....which actually sucks more than having one but not doing a recall, as means that the new ones are just as likely to fail I guess.

When I asked at Jim Aims last time the bloke said it wasn't worth replacing mine if they were fine as the new one's might not be better The bloke this time was of the opinion it's not a bad idea to change as typically they go as they wear so better to have new ones than take the chance.

IMO it's a no brainer to get the arms replaced whilst they're in there.

Yes that's my thinking. I'm paying them to do the valves I might as well get them to do the rockers whilst they are in there. And in spite of the above I think it's probably worth doing as mine have done 12k now so hopefully new ones will be better.

Hmmm, i'm sure the service guy told me the new ones are different? Something about different design and end float springs to mind, but I could have it arse upwards and I'd willingly concede a dealer should know better than me. That said, if the replacement ones are no different, why do they agree with replacing them as a precaution?

Could be I'll ask. The bloke I spoke to was the service front end guy rather than the mechanic when I went in last year. Although he could be talking about the twin balancer version in the 2016s on, but that's a totally different valve train and wouldn't work on my engine.

This time, and I think it might be the mechanic that did my snapped bolt who answered the phone, he said they can show signs of wear over time so new ones should help.

It's booked for the 1st so I'll call the week before and make sure they have some in and double check it's a good idea.

The other shop I asked as was the KTM centre a while back. They seemed to imply it's luck of the draw with rockers, some go, some don't. Their opinion was that if mine were fine leave them. Hence a bit of my indecision.

[ogri]

Ask for your old ones and if ok keep as spares?

[Taipan]

I've read that but asked at 2 different KTM dealers and they claim there is no updated part....which actually sucks more than having one but not doing a recall, as means that the new ones are just as likely to fail I guess.

When I asked at Jim Aims last time the bloke said it wasn't worth replacing mine if they were fine as the new one's might not be better The bloke this time was of the opinion it's not a bad idea to change as typically they go as they wear so better to have new ones than take the chance.




Yes that's my thinking. I'm paying them to do the valves I might as well get them to do the rockers whilst they are in there. And in spite of the above I think it's probably worth doing as mine have done 12k now so hopefully new ones will be better.

Hmmm, i'm sure the service guy told me the new ones are different? Something about different design and end float springs to mind, but I could have it arse upwards and I'd willingly concede a dealer should know better than me. That said, if the replacement ones are no different, why do they agree with replacing them as a precaution?

Could be I'll ask. The bloke I spoke to was the service front end guy rather than the mechanic when I went in last year. Although he could be talking about the twin balancer version in the 2016s on, but that's a totally different valve train and wouldn't work on my engine.

This time, and I think it might be the mechanic that did my snapped bolt who answered the phone, he said they can show signs of wear over time so new ones should help.

It's booked for the 1st so I'll call the week before and make sure they have some in and double check it's a good idea.

The other shop I asked as was the KTM centre a while back. They seemed to imply it's luck of the draw with rockers, some go, some don't. Their opinion was that if mine were fine leave them. Hence a bit of my indecision.

IIRC the guy suspected that low oil levels could be a cause, as these engines do use oils and if it got low it certainly wouldn't do it any favours. I also remember him saying about if checked for play regularly they can normally be caught in time and most of the broken ones they'd seen were on home serviced bikes, where all they got were oil changes. I guess they aren't Jap bikes and do need a more stringent service detail?

[mangocrazy]

The 690 engine only has a tiny amount of oil (1.7 litres, as I recall) so checking oil levels regularly is vital. Before every ride is the best regime. Mine's the 2016 on engine with top end balance shaft, so interested to know how these fare. You'd hope that KTM took the opportunity to design out a weakness, but knowing KTM they could just as easily have designed in a new flaw...

[Supermofo]

IIRC the guy suspected that low oil levels could be a cause, as these engines do use oils and if it got low it certainly wouldn't do it any favours. I also remember him saying about if checked for play regularly they can normally be caught in time and most of the broken ones they'd seen were on home serviced bikes, where all they got were oil changes. I guess they aren't Jap bikes and do need a more stringent service detail?

A couple of years ago I spoke to a mechanic at the KTM Centre, he used to race 690's in Oz before moving here. He reckons all of the failures he'd seen were due to low oil or not servicing the bike properly. He said most he'd seen that had gone were on pretty abused bikes and most 690's had no issues. Hard to know though.

I'll see what Jim Aim's say.

[Supermofo]

The 690 engine only has a tiny amount of oil (1.7 litres, as I recall) so checking oil levels regularly is vital.

Yes I check mine a lot. Not every ride now, as I've owned it for 5 years and it's usually only every 350 to 500 miles that mine might need a top up. But I keep mine nearer the full mark as much as poss plus I always warm the engine before riding. Mine seems to have used less oil as it's got older.

[mangocrazy]

I have a theory that over-gently running in means the rings don't seat properly and oil gets past the rings. Also I changed my oil twice in the running in period and used running in oil when I changed it. This also promotes proper bedding in of all surfaces. I handed it over to the dealer at nearly 800 miles after which they put in the reassuringly expensive fully synth Motorex stuff.

[Supermofo]

When I bought mine new Jason said don't redline it but up to 6.5k was fine pretty much off the bat (think mine red lines at 8) and then work up to the red line by first service. To be honest I rode it pretty much normally from day 1. I don't recall having to put any top up in at all before the first service.

Sometimes I can do a 400 miles in a weekend and use none, other times 400 miles in normal casual rides over a few weeks and it'll need 100-200 mls.

[mangocrazy]

Sounds like you ran it in similarly to me. I never let it labour and always kept the engine spinning. Not sure if yours was the same, but the tacho on my TFT display flashed red when you went over a pre-set limit (can't remember what it was). By the end of the running in period it was flashing red most of the time...

I know the revised engine with the 2nd balancer shaft was supposed to let it rev out more, but the dyno readout on mine made it clear that hanging on after 7k wasn't the best way to ride it. Far better to change up at 7k and ride the fat part of the torque curve,

[Supermofo]

No mines got an old fashioned wind up rev counter

[weeksy]

_DSC8576_zpsid5j4jtf by Steve Weeks, on Flickr

Nowt wrong with the early ones

[Le_Fromage_Grande]

I have a theory that over-gently running in means the rings don't seat properly and oil gets past the rings. Also I changed my oil twice in the running in period and used running in oil when I changed it. This also promotes proper bedding in of all surfaces. I handed it over to the dealer at nearly 800 miles after which they put in the reassuringly expensive fully synth Motorex stuff.

The main thing with running in is to not let the engine get too hot, doesn't matter if you do it fast or slow, what your trying to achieve is taking the high spots of the rings and bore (and other surfaces), the faster you run the engine the less running in miles you'll need, changing the oil often is a good idea as it get's rid of the debris in the oil.

But do modern engines need running in, I thought it was something that was no longer required now the parts are made much better than they were 30 odd years ago.

[Supermofo]

But do modern engines need running in, I thought it was something that was no longer required now the parts are made much better than they were 30 odd years ago.

I think you're right. I was told to just not labour the engine. The worse thing they told me I could do was lug the engine at 3.5k or lower, the 690 really doesn't like that. But to be honest you get that as soon as you ride it, like all singles low revs don't work at all. And the 690 more than most singles really thrives on revs, it's not like an old school thumper at all.

[mangocrazy]

Yes, tolerances should be so much better than they were so you could assume that running in was unnecessary. But I was told that it's the microscopic imperfections and high spots that you're taking off, not the massive craters and peaks of yesteryear. So I guess running in is still required, just not as carefully and not for as long.

But as you say, the absolute worst thing you can do to a 690 is to lug it at low revs. They really don't like it and they let you know in no uncertain terms...

[Supermofo]

After my 40 miles last Fri I left the battery in the bike deliberately and then started it yesterday. I actually didn't think it was gonna start as I hit the button and got a wuurrrrrh rather than a nice heathy spin, but it fired before I had time to take my finger off the button, so it did actually start. Got the Soft 4.1 Dat error code on the dash. So I think that confirms the battery is knackered.

I bought the battery in and charged it anyway and oddly it was showing at the higher end of health and only charged for about 15 mins before going on to maintain but think it's day is done.

Had a look on Wemoto and Halfords and looks like the OE Yusa YTX9-BS is only £50 so that's a result at least. Struggling to find the right option for a Motobatt, but given the ease of getting the Yusa and the fact it's lasted 5 years 12k miles I think I'll probably go with what I had.

[bevvo]

I usually get batteries from tanya on ebay. 24 hour delivery and cheap. Theres usually a couple of options with the price/warranty ratio. E.g a powerline for yours is £26.

[Supermofo]

I usually get batteries from tanya on ebay. 24 hour delivery and cheap. Theres usually a couple of options with the price/warranty ratio. E.g a powerline for yours is £26.

Interesting they list a different battery to what mine has in it

This is my battery and only £35 from here, cheers
https://www.tayna.co.uk/motorcycle-batt ... a/ytx9-bs/

This is what they list for mine
https://www.tayna.co.uk/motorcycle-batt ... sa/ytz10s/

Or a Motobatt
https://www.tayna.co.uk/motorcycle-batt ... t/mbtz10s/

Their listed batteries look to have higher capacity and CCA (what's that cranking amps?) so would I be better off with them? 190A vs 135A

Having said that not had issues with mine for 5 years.

[bevvo]

Yes CCA - something to do woth cranking amps. I seem to remember that being important on bikes that may suffer with sprag clutch issues i.e. the higher the better.