2007 TE with 300 kit and intermittent fault

[spyshadow]

Hi all,
New to this site and new (to me) Husky owner, 2007 250TE with a 300 kit on it. have had a few teething problems.The bike looks to have been reasonably well looked after.

1. flat spot from idle to wrapping it on. It appears from viewing previous posts that I'll be able to sort this out with jetting kits, and a bit of homework.

2. My BIG question is, What will cause it to randomly cut out when riding? then takes 5 -10 minutes of furious kicking and inventing new language, and will then suddenly start, sometimes only to run for a couple of seconds, sometimes will run for 20 minutes.
It is just like someone reached over & pushed the kill switch. Obviously that was my starting point, I have checked kill switch and electrics back through the loom, for loose and broken wires, = nothing.

Pulled carby apart, cleaned bowl, checked jets, float height, every thing is still standard, so I suspect this will be where I start for the flat spot issue, but still nothing pointing to why sudden death.

I have both owners & workshop manual, The issue feels like an electric fault, The workshop manual shows the "gear position switch" with a resistance value next to each gear selection, I have a mechanics quality diagnostic meter that shows very accurate readings. when set up I have all the readings with-in spec, however, randomly when I go through the gear selections, the resistance value will go off the scale.

What does the gear position switch do? I'm assuming it sends resistance values to the cdi unit confirming which gear your in, so it knows what performance is required.

If this is the case, is it possible? or has anyone else experienced sudden death from similar issue??
I then started to get deeper into the fault.
I took the gps out and checked the brass pin at rear and the spring, all in good condition, I then performed the same test with the gps off the bike, could not get it to fault, at all. I even put the hair dryer on it to warm it up to operating temp, still NO fault, readings all stayed with-in spec

I refitted gear lever, with out gps and went through gear selections. I then set up meter and tested earth continuity through plate at rear of where gps sits (with spring and brass pin) taken out, and 1 x probe on side of mini shaft where spring sits, and 1 x probe back to neutral at battery.
THIS appears to be the problem, I'm getting really weird readings off what is essentially just part of the earthed frame / motor.
I then ran separate earth to frame, no difference to weird readings.
What is behind the plate at the rear of the gps, is there another connection, other than friction that could be broken/ fractured?

I understand that the readings will be coming through 'the oil', 'the bearings' etc and will give off possibly higher readings, but why have such specific values next to each gear selection if it can be so randomly altered.
I've purchased a new gps (on its way from Austria), but now I'm definitely not convinced that gps is the issue, due to the extreme resistance readings I'm getting from plate at rear of gps
It's doing my head in.

Am I chasing the wrong "fault ?


any assistance greatly appreciated

spyshadow

 

[Flash319]

Sounds like you have 2 issues. The flat spot sounds like a jetting issue and the cutting out electrical. Check the resistance values for your ignition coil. Also do the obvious and change your spark plug. Check Throttle position sensor as well.

 

[spyshadow]

Thanks for the reply, (I'm thinking along same lines (re 2 x separate issues) I have double checked coil & all good, also now have couple of spare new spark plugs, ready for the big moment.
I'm really disappointed that I didn't take readings off TPS before I pulled it apart, however I'm positive its set correctly for the refit.

When I take resistance readings off the brass pin and spring or, from with-in the shaft behind the gps, which houses the brass pin and spring that makes contact with the resistance points on gps, that's where the weird readings originate. However, when I apply firm pressure to pin and spring or directly push probe firmly onto internal of shaft, the readings drop back into spec.

I'll get a mate to make a copy of brass pin approximately 1mm longer to ensure firm contact (rather than stretch spring)

I have gone through all pull-apart electrical plugs and found that PO must have taken it through some serious wet stuff, the bike was really clean to look at, but when you start pulling apart stuff!!! (every thing has a coating of mud on it, or in it) lots of fiddly cleaning with emery cloth, I have then used a silver electrical contact paste on all connecting blocks (not too much or it'll defeat the purpose and have contact everywhere)

It pays to have a mate take a second look at what you've done.
I missed a couple of wires with damaged insulation that had been incorrectly run under petrol tank.

I'm feeling a lot more positive about the repairs, I have a set of accelerator cables on order, (broken strands, at carby) as soon as they get here, I will complete assembly and take for test ride.

Will keep updated


spyshadow

 

[spyshadow]

I have solved the gear position switch issue.

I was unable to get access to a lathe, so I inserted some brass threaded rod into drill press and with a couple of good files was able to shave rod down to new size, then graded wet and dry to a perfect finish.

I ended up with a brass tip (looks similar to slightly smaller than a .22 bullet projectile) I then turned down the the rear end of tip to allow firm 'push on' fit into spring, at the other end of spring, which originally just sat against the internal rear end of shaft in selector drum, I made a similar brass tip but instead of a dome head it is flat and only 1.5mm thick, also with a turned down shaft with a firm fit into spring, This now gives me good conductivity to allow accurate resistance readings.

The overall length has increased by 3.5mm however there is still travel in the spring length to compensate any movements laterally by the selector drum.

I have reassembled and tested and have not been able to get system to fault, (previously it was all over the place, at times off the scale = open circuit)

What I haven't been able to establish and no one has been able to confirm, is:

How important are the readings from the gear position switch?? could it even be the cause of flat spot??

Everybody goes straight to the carby!! to resolve the issue, If the readings are showing open circuit, as it was randomly showing, its basically telling the CDI your in neutral, and that you should be at idle or that your in 6th gear, but in reality you were in 1st

Have I just solved a problem that wasn't critical? ( I believe it has to be, otherwise why are the gps resistance readings so specific for each gear?)

Still waiting for delivery of accelerator cables, before I can track test.

I'm hoping that the above fix and the previous electrical connection remedies will complete the repair.


spyshadow

 

[Flash319]

Ignition runs with a base spark advance map. Gear position, Throttle position move the map around (how much advance at what rpm) to try and optimize the spark timing. The bikes do not have any sort of engine load sensor (Map, air flow...ect). I would assume that is what the gear position sensor sort of does. Tells the CDI how much load to expect and shift the spark curve up or down a bit.

If you disconnect all input sensors to the CDI you should be stuck on a base map that does not shift up or down. This may cause a flat spot at a certain RPM but I would guess that you would not notice to much (you would if the bike was FI). You ARE noticing so I would be looking at fuel issue (carb settings, service). Bring your needle up a bit (drop the clip one notch).

The way I look at it is if the bike runs and will rev to red line your ignition system (cdi, coil, sensors) is prob good. There may be a problem with them but I would start elsewhere first.

 

[spyshadow]

Thanks for the info Flash, I now have the needle sitting at 4th slot from the top, originally was 3rd from top (so I've lowered one) Hopefully I'll be able to detect increase or decrease in performance and work from there.

Slightly shattered that I spent too much time messing around with gps on wasted mission, I think I'd talked myself into believing I was on the right path.

Will keep looking.

Doesn't matter, it's all a learning curve, as long as I don't loop out, it's all good.

thanks

 

[spyshadow]

Finally**************************************** mission accomplished,
After many hours, and a non essential purchase of new gear position switch,

The intermittent fault is fixed.

I had the bike on a ramp lift, with a temporary fuel tank suspended above bike, the wiring loom was opened up, access to gps and every other molded connection plug at the ready, multiple volt meters and testers connected, note pads with all sorts of readings and colour codes for wiring repairs that had been done over the years, it looked like the husky was in an intensive care unit.

Tested all the components, and had to also open up the wiring loom, which has had some professional repairs done over the years and also some dodgy work, disconnected and re-done any wiring work that suspect.

Then started on the fuel system, found some gunk in the carbi bowl, cleaned and reconnected, with new fuel, tested,...ran good for a bit then died, then started again, then ran rough, pulled carbi apart again...... more gunk, so then had to clean tank & fuel line, then install in-line filter.

Started,.. all good........ for a couple of minutes then died again, more testing, tweeking, fiddling with junctions and connections, eventually traced it back to the coil, the push on spade lug was NOT firm connection, cut off, crimp new lug, and runs like new.

(I had that out, and bench tested the coil, and just about every other electrical component) BUT had missed the simple fault of poor contact from spade lug.

Anyway, it gave me a chance to fix several other issues that were due to expand into other areas.
So it's had a good going over, and hopefully will get some trouble free run time.



Thanks to all for suggestions and input

spyshadow