My KR250 Project

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Bogan
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Post by Bogan »

Still more progress, not as much as there was going to be but some important things have still been done this weekend.

Cleaned the chambers out with some petrol, to get all (or most of) the oil sludge out. The caustic soda treatment to remove the carbon will come soon, but they've been cleaned up inside and out with some fuel and it removed lots of gunk from both inside and out:

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I was blowing them through with compressed air and little bits of this came out, it's no big deal right?

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So while the chambers were drying I fished around with the electrics, doing some little or low cost things while I don't know if it will run right. I found the wiring for the front blinkers and rear lights under some black tape:

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And I also found bits and pieces of the number plate light and rear lights in the box of bits so I don't have to figure if this stuff is available new:

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And three of these in reasonable nick were in the box of bits too:

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The fourth one that I have looks to be a little dodgied up and semi permanently connected to the front fairing already:

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I figure once I get it running again I can plug it all in and see how much of the electrics works, I know the horn and kill switch work, I can just hope that all the other wiring and switches work, and maybe I might just have to replace a bulb or two...

:D :D :D
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Post by StrokerBoy »

Bogan wrote:I was blowing them through with compressed air and little bits of this came out, it's no big deal right?

Image
No, baffles only slow you down, put those bits in the bin. :mrgreen:

Chris Dupen of Netbikes Australia had boxes of new KR winkers a while back, see if he has any left.
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250 drummie
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Post by 250 drummie »

You can buy new indicators complete, copies I think but may be NOS from a guy in Sydney.
Bogan
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Post by Bogan »

So after a bit more than 48 hours full of caustic soda I rinsed out the chambers tonight, and had to rinse my arm and leg off too (oops).

Anywho, I haven't dried them out, or rinsed them with vinegar to neutralise the alkali, but here's a before and after shot of the caustic soda mix, 500g of NaOH to 1.5 litres of water:

Before:

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After:

Image

:mrgreen:
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ScottaKR
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Post by ScottaKR »

Looks like it may have cleaned a little of the gunk out. :shock:
Think I may have to treat some of my pipes after looking at those results.
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Post by StrokerBoy »

My Dad bought me a secondhand DT50 just before my 16th birthday. It was horribly strangled, and we soon found out that the exhaust was clogged up. Did this by loosening the pipe where it mounted to the cylinder - it ran fine like this but by christ was it loud. :lol:

Did the old caustic soda treatment and got similar results to you. But sadly it made little difference, and we had to saw the silencer in half and chisel out all the cack (and the baffles :mrgreen: ) by hand, then weld it back together.

Not suggesting you'll have to do that though, always gonna be much worse on a restricted moped with convoluted offroad-style pipe.

Looking forward to hearing your KR running on two soon. Carry on ! =D>
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Bogan
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Post by Bogan »

OK so the exhausts got cleaned out and the carbies got disassembled and cleaned out and it still does this:

http://www.youtube.com/watch?v=aENRmGMoXMw

The back exhaust is hot, and the front is obviously doing something, could it be the oil pump circuit that's faulty and it's flooding the front cylinder with oil and making it chug?

:-k
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ScottaKR
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Post by ScottaKR »

Pull the plugs out (I assume youve fitted new one by now) and make sure they arn't fouled up. Check again that they both have spark.
Have you checked the compression on both cylenders?
Also, when you cleaned out the carbs and re-connected them, did you make sure they were syncronised?
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Bogan
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Post by Bogan »

ScottaKR wrote:Pull the plugs out (I assume youve fitted new one by now) and make sure they arn't fouled up. Check again that they both have spark.
OK, I assume they would given that both exhausts are hot when it runs but I'll check anyway.
ScottaKR wrote:Have you checked the compression on both cylenders?
Nup, not at all, should do that I guess, do I do that with wide open throttle just kicking it through a few times?
ScottaKR wrote:Also, when you cleaned out the carbs and re-connected them, did you make sure they were syncronised?
Nup. Synchronised how?
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ScottaKR
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Post by ScottaKR »

Bogan wrote:
ScottaKR wrote:Have you checked the compression on both cylenders?
Nup, not at all, should do that I guess, do I do that with wide open throttle just kicking it through a few times?
Throttle fully open with the engine warmed up (if not warm you could put some 2T oil down each plug hole to help the rings seal properly). Should be between 107 and 164psi according to the manual.
Bogan wrote:
ScottaKR wrote:Also, when you cleaned out the carbs and re-connected them, did you make sure they were syncronised?
Nup. Synchronised how?
OK, if you don't already have a workshop manual you can download each section individually from here.
Basically, you want to make sure that they're both open the same amount, and that theyre opening at the same time when you twist the throttle.
I'd suggest reading through the whole fuel system section of the manual and then checking your carbs again, including the float height as this can cause flooding.
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KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)
Bogan
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Post by Bogan »

ScottaKR wrote:Throttle fully open with the engine warmed up (if not warm you could put some 2T oil down each plug hole to help the rings seal properly). Should be between 107 and 164psi according to the manual.
Right you are, will give this a go next weekend.
ScottaKR wrote:Basically, you want to make sure that they're both open the same amount, and that theyre opening at the same time when you twist the throttle.

I'd suggest reading through the whole fuel system section of the manual and then checking your carbs again, including the float height as this can cause flooding.
Yeah I have a manual, it was one of the scores that came with the bike :). I know what you mean about synchronising now, will pull the intake rubbers off and check it out, also next weekend :).

Cheers. I figure if I can eliminate a dozen things then it's a dozen things the workshop won't have to do when I take it there if I can't get it sorted.

Rear carby is still overflowing, looks like I'm up for a needle and seat (I did both the float heights when I had them apart not long ago).
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Post by pablo »

Glad to see you were wearing your safety flip flops during that demonstration Bogan :D

Good man =D>
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Post by JanBros »

ScottaKR wrote:
Throttle fully open with the engine warmed up (if not warm you could put some 2T oil down each plug hole to help the rings seal properly). Should be between 107 and 164psi according to the manual.
why would you do that ? the purpose off the test is to know how much compression the engine has, not artificialy raise the compression so one can be happy with the artificial result :wink:
ScottaKR wrote:Also, when you cleaned out the carbs and re-connected them, did you make sure they were syncronised?

OK, if you don't already have a workshop manual you can download each section individually from here.
Basically, you want to make sure that they're both open the same amount, and that theyre opening at the same time when you twist the throttle.


true, but that won't be the problem her. bas synchronised carb's mean that one won't open as much as the other, and so that means that that cylindre isn't performing as well as the other.
but they both should still work ok, and the engine should rev nicly :!:

the heavy smoke suggests a bad cranckseal to me, but still the engine should rev on the other cylindre :idea:

I'd try to run the engine on 1 cylindre alone, trying each one seperatly. that way you'll now if they both perform as good/bad as the other, and you can determine if you have a problem in one cylindre, or that it is related to the entire engine/electronics/....
Last edited by JanBros on Tue Mar 01, 2011 1:01 am, edited 1 time in total.
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ScottaKR
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Post by ScottaKR »

JanBros wrote:
ScottaKR wrote:
Throttle fully open with the engine warmed up (if not warm you could put some 2T oil down each plug hole to help the rings seal properly). Should be between 107 and 164psi according to the manual.
why would you do that ? the purpose off the test is to know how much compression the engine has, not artificialy raise the compraision so one can be happy with the artificial result :wink:

It's not about getting a false reading that will make you happy.It's only something you may do if you cant get the engine running. The idea of getting the engine warm is so that all the metal has expanded to normal running parameters, as well as haveing an oil film up the bores and on the rings. If the engine hasn't been warmed up or run at all, the figures would read much lower than normal.
JanBros wrote:
ScottaKR wrote:Also, when you cleaned out the carbs and re-connected them, did you make sure they were syncronised?

OK, if you don't already have a workshop manual you can download each section individually from here.
Basically, you want to make sure that they're both open the same amount, and that theyre opening at the same time when you twist the throttle.


true, but that won't be the problem her. bas synchronised carb's mean that one won't open as much as the other, and so that means that that cylindre isn't performing as well as the other.
but they both should still work ok, and the engine should rev nicly :!:

the heavy smoke suggests a bad cranckseal to me, but still the engine should rev on the other cylindre :idea:

I'd try to run the engine on 1 cylindre alone, trying each one seperatly. that way you'll now if they both perform as good/bad as the other, and you can determine if you have a problem in one cylindre, or that it is related to the entire engine/electronics/....
Once again this is just from my limited experience, but badly set-up carbs could be causeing one cylender to flood while the other is lean. This is almost certainly not the whole problem, but is something that should be addressed at this stage so that we're not trying to diagnose something that could be in reality 3 different problems.
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Post by JanBros »

ScottaKR wrote: It's not about getting a false reading that will make you happy.It's only something you may do if you cant get the engine running. The idea of getting the engine warm is so that all the metal has expanded to normal running parameters, as well as haveing an oil film up the bores and on the rings. If the engine hasn't been warmed up or run at all, the figures would read much lower than normal.
in my believe , they would still be more accurate . maybe MJ or TSI have more info :?:

ScottaKR wrote: Once again this is just from my limited experience, but badly set-up carbs could be causeing one cylender to flood while the other is lean. This is almost certainly not the whole problem, but is something that should be addressed at this stage so that we're not trying to diagnose something that could be in reality 3 different problems.


I was just referring to the synchronisation part :wink:
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