A bit of 1200TS problems.

All right, so looked a bit more on the 1200TS tonight.

- We changed engine oil. No hydraulic Lock ;)
- We installed a new clutch hose (braided) and a repaired clutch cover, and no copper washer at the clutch cover end of the line.
- all cables free and routed correctly and free moving. No lifted choker plungers.
- Battery recharged (Odyssey).
- All fuses cleaned and fine.
- Earth point under saddle under one frame rail cleaned, fine.
- Bosch ignition boxes cleaned up at the connectors and fine.
- Carbs ultra sonically cleaned and new hardware inside, slides 60/2, needles K1, Main jet #125, idle jet #65, adjusted floats to 
  18mm, new pilot screws (idle mixture) and set to 1? from bottom, all new gaskets. Needles set to middle notch.
- all fuelfilters and tabs clean and fresh fuel pouring.
- no air filters at all today.
- inlet tracts looked over, new O-rings etc. reinstalled.
- ran without fuel tank cap.
- 3 new plugs.

None of it made any difference. Problem is taking gas from around 3000 rpm upwards, both when standing still and when driving. Splutters and hessitates, almost not doing anything. Stalls and then resettle if onelet go of the gasroll. Starts immediately and runs fine under 3000 rpm.

New parts to be installed Friday are 3 new plugs (Again) - NGK B8ES, and 3 new 5 KOhm spark plug caps.
I wil also look at pickups and pick up gap on Friday. Is that the same as on a SFC1000? (distance).
I'll also reset the carbs and tune them in on Friday as well. Couldn't do more tonight as it got dark.
Meanwhile I borrowed an ignition strobe light, so will try to read up on how to test that on Friday.
If I find nothing there, I will possibly install my own SFC1000 inlet stubs and complete carb battery to see if there's any difference.
If no difference, I'll see if I can change the spark plug cables. By the way, this 1200TS's got White coils (not the red/Brown ones) from new. Still on.
If no difference, I will probably install a set of Witt MK II ignition.

It's pretty annoying.

Kind regards,
Jacques
 
One thing you don't appear to have done is strobe the ignition. One of the first suggestions back at the beginning of this thread was that maybe it's not advancing properly. Those old Bosch ignition systems are well past their prime, so it wouldn't be surprising if one or more of them is not working properly. So I'd be checking the spark timing if I were you.
 
It apears to be on all 3 cylinders that it won't pick up on revs. It will, albeit slow, very slow, and you have to twist the throttle to max to slowly rise the revs.

On my former RGS the ignition Lock/switch burnt off. Haven't looked at this, but it seems to be stable in function. I'll take it apart, though.

Kind regards,
jacques
 
Fuel flow not only from fuel taps but when you remove the float bowls?

No obstruction in the airbox?
Or the exhausts?

Just trying to give you a checklist to go through.
 
Worked a bit on the 1200TS today.

So, marked up all points of the timing related to the ignition, and conencteda  strobe to see if it was times correctly. It is times correctly, and ignition advanced as it should.

Then I looked at the spark plug caps, as I had found them to be somewhat Loose on the plugs, so I had ordered 3 new NGK 5 KOhm spark plug caps, and installed them today. I measured them all three to be 4,733 KOhm.

THe bikes starts promptly as usual, and after Warming up (again), my friend drives it up and Down the road. It still have the same problem, you cannot give gas and have the engine rev. It's very slow to pick up revs after 3000. BUT there's something new, though.
Now it's a bit more willing after 3000 rpm, up to around 4000 rpm, but rev counter cable now broken. Ordered a new one, and although still the same problem, it seems as if it is more willing. I have adviced him to change all spark plug cables asap. Bike now idles pretty well and silent and vibration free. Well for a 180 that is ;)

Since this made a difference, although small, but noticable, I took off the carbs and brought them home tonight. I took the fuel rail off, together with the pieces of fuel hose to each "fuel banjo", one on each carb. Under those, my friend asured me, was clean and new. Well, not so. It's been cleaned last Autoum, new hardware and ultrasonically cleaned and stored since then. Even since July this Summer, it have become worse. I tend to think the lousy 95 God knows only where he got, is damaging everything. I have never seen so rapid breaking Down of gaskets and brass. Shocking really!!!
I just wrote him to CLEAN the gastank tomorrow, while I'm on job.
The fuel filters on the carbs were semi gunked with a brown'ish powder. He only use modern cow fart 95 Octane fuel from whoever sell it. I religiously use ONLY Shell Vpower 99. I have no gunk anywhere. and no corrosion or green or Brown brass in the carbs. Never. I swear they were okay in July when I cleaned them.

The "fuel banjo's", connectors, to each carb also had small "piles of brown gunk in them (they are black plastic and from last Summer, 2017, when I put them on). I cleaned them out and reinstalled together with 3 new fuel filters as even the white plastic on the 3 fuel filters seemed to have been damaged by fuel and humid air, as they have become brittle.

Then on to the carbs themselves. I rebuilt them last Summer with new gaskets, brass etc, and now every single bit were green or dark matte or Brown. Shock! The O-rings that protrude into the float bowls were a bit destroyed by fuel it seems. I will install 3 new ones when I get my hands on another set.
The floats themselves measured 18mm precisely, but I took them off and upon carefull inspection, the two individual floats seemed a bit twisted compared to the metal fork/axle they sit on. So everything bent back into place. the bent forks seemed a bit too open for my liking and were pressed back to more normal shape. The three pins that suspend the floats, were very worn. I changed those also to a new set I had. All reinstalled. The 3 floats now measure 18mm precisely again, but seem more "springy" - kind of more ready. Just like new floats do. The 3 small needle valves above are new already. No problems with rubber tips or springs. Black rubber tips though. I like the red ones better, but cannot get them any more.

I then recleaned the float bowls, all channels inside carbs, and various bits and bobs with brake cleaner, and it seems there is hole through all over, as it should be.

Tomorrow hopefully, I can reinstall them and testdrive.

I think this problem is a complex mix of multiple small problems that lead to the way it drives, mainly caused by bad fuel and long storage in a very damp garage. I adviced him NEVER to use it Again. He just built a new garage at home, so that should be solved ;)  Starts fine, runs fine on idle and up to around 3000. Now, after today Thusrday, around 4000 rpm, so an improvement.

I also found the choke handle itself to be much too tight, so that it does not flip back by itself. Mine is a bit Loose, so it returns by itself. I ONLY use it to aid start, NOT warm up or anything else. Now I adjusted the choke on the 1200TS to be similar.

Finally, I adjusted the idle mix screws to only 1 1/4 then later evena  bit less. Seems to run better. I'll redo all tomorrow after Work when reinstalling everything and tank have been cleaned out.

Reply: there is no airbox on this bike. There were 3 K&N oval pod filters. Those are also renewed completely, despite the old ones having been cleaned and very lightly oiled with K&N filter oil. Not on the bike right now. Will be reinstalled when problems are solved.
So, tomorrow I'll reinstall the carbs, then balance, then finetune idle mix screws and then rebalance again.

Will report back here on how it runs.

Kind regards,
Jacques

 
SO, todays Work consisted of:

* recharging battery to full.

* reinstalling carburettors on to inlet tracts, cables etc.

* emptying tank and clean both fuel tab filters. Semi-dirty.

* new plugs again NGK B8ES.

* installing air pod filters (new).

* idle mix adjustment folowed by sync of carbs at 2000 rpm, then sync at 1200 rom, then Down to idle at 1000rpm.

The bike started very easy (as always) and idled very nice and calm and vibration free.
A testdrive showed more willingness to rev and to pick up revs above 3-4000 rpm.
Still same problem, but surely closer.
The bike can now pick up 8000 rpm if you moce the throttle slowly and easy.

So, we looked at acceleration pumps, and all 3 were dry. No extra fuel were injected. So, that is NeXT step to look at.
Two electrical connectors to resistors NeXT to ignition coils were a bit Loose. Tightened them a bit.

I think we are getting closer.

Will report back, once I've had a chance to make the acceleration pumps Work Again.


Question; how can I test the ignition HT leads when installed (and glued into coils)?

Kind regards,
Jacques
 
I think you can exclude the accelerator pumps as part of this problem. Many people have eliminated them entirely (me included) and have noticed NO problems with wide open throttle, roll-ons, low-end response. By all means, make them work, but I think you can safely look elsewhere for resolving this issue.

Borrowing parts from a donor bike is an excellent way to track things one-by-one. i once resolved a problem with my partner's 250 kwaka, running on one cylinder, by fitting the big Bosch coil from my SF to it!
 
redfox said:
The bike can now pick up 8000 rpm if you move the throttle slowly and easy.

I usually agree with Quentin (Piranha Brother 2) but in this case I think the accelerator pumps might be relevant.

The bike is now starting, idling and revving out OK, so your high and low speed jetting seems OK. But only if you open the throttle slowly. I'm guessing that if you whack the throttle open quickly, the engine bogs down and hesitates. That's typical behaviour for an engine without accelerator pumps.

If the bike has Dellorto carbs, the accelerator pumps are above the level of the float bowl, so they have to suck the fuel up from below. Although the diaphragm pumps are of the positive displacement variety, and should self-prime, sometimes the little pump valves don't seal very well when they are dry (as they would be when you've had the carbs apart) and the pump won't be able to suck the fuel up, so you have to prime them.

There's a brass screw on top of the accelerator pump on the intake side of the carburettor body. It's a plug that when removed allows access to the pump chamber. Remove the plugs from each carby, use a squeeze bottle or syringe to squirt a little fuel into the holes (until it overflows), then replace the plugs. That should be enough to prime the accelerator pumps and get them working again.
 
Untill yesterday, all testruns, starts etc. have been without any air filters. Only yesterday, we installed new K&N pod filters.

Thanks for the acceleratorpump tip. I'll try that asap, possibly tomorrow.
If that does not produce any results, my own carbs incl. inlet tracts, are being moved onto his 1200TS to se what happens. Will report back.

Kind regards,
jacques

Kind regards,
jacques
 
I have told this story a few times.The TE 350 4 stroke Husky I had ran a Delordo carby. It had a snatchy action that caused issues when you needed fine control so I removed the plastic actuator from the slide,that did a few things. It made the throttle MUCH lighter and gave a beautifully soft action with great fine control.BUT it also made the bike imposable to wheelstand,it lost the massive punch it had off idle. Moving the throttle aggressively and the bike would just fall on its face. I reinstalled the accelerator pump actuator and the punch was back. You could ride around this lack of punch on a lot of bikes but not on a dirtbike thats does hard single track.
 
Worked on the accelerator pumps last night, and all 3 are now working.
Testdrove and no good, still hessitates after 1/3 movement of the gasroll. Slow movement makes the engine spin up better. Not really drivable with that way of doing things.

In fact it appears as if putting on the K&N air filter pods (large oval ones) strangled the inlet some. It feels like it drove better without airfilters.

How far turned in is it possible realistically to safely run with the idle mix screws?

It's got new #65 idle jets. Should we try a smaller one, say 62? When we tried to run a smaller main jet, #118, it was the same problem. Now back on #125.

Anyway, I think that is not the main problem. I told him it's time to measure spark on each wire, look at the pickups and adjacent wires, as well as installing his Motowitt Mk II systen, plus change spark high voltage cables.

Any ideas?

Kind regards,
jacques
 
I can only repeat it sounds like starvation.
If removing the filters did not cure it then the carbs themselves must be at fault.
Is it possible to fit another set of carbs to see if it eliminates the problem?
 
Yes, Grant. I will install my ownset incl. inlet tracts to see what happens.
Just waiting for a bit of dry skies. And home from work  ;)

Kind regards,
Jacques
 
I did this once to diagnose a hard to identify problem.
Despite the carbs having had several hours in an ultrasonic bath and blown through with an air line it still would not run right.
Anyway, swapping to a known set of good carbs pointed the finger directly at the original carbs.

In the end I replaced the carb bodies and the problem went away. Must have been either some casting issue or a blockage deep within.

 
redfox said:
Worked on the accelerator pumps last night, and all 3 are now working.
Testdrove and no good, still hessitates after 1/3 movement of the gasroll. Slow movement makes the engine spin up better.
I rest my case, your honour (Cam)  :-*
 
Okay, so he's gone for the week. No more fiddling this week. But we found a single wire leading to one of the resistors, that were broken. So repaired that, he took a test drive, and now it drives nicely with strong pull in 1'st and 2'nd gear. Giving full throttle in 3'rd, 4'th and 5'th does not produce much, except strangleing, then slowly picking it up and finally speed. I hope this came through clear.

He wants to ride for a longer trip on Sunday after getting back. Will report back then.

Kind regards,
Jacques
 
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