1979 Suzuki TS185ER high speed coil?

[blurredman]

Hi Guys,

I've had the bike for about 4 years but have used it on and off because of a problem I'm only now seriously looking into.


When using the bike, anything up to 5k rpm it runs fine, at least under load.

If I get to 'about' 5k rpm the bike behaves like it is missing- you hit a kind of 'wall' and the bike refuses to rev out, almost like it has a rev-limiter on it. This is most prominent at lower gears. At higher speeds it can't rev past 5.5/6k


I have done the following to diagnose:

-Cleaned out carburettor- making sure to clean emulsion tube jet holes, jets are standard and needle height is standard, and checked float level.
-Checked/cleaned/oiled air filter
-Changed Spark plug and coil + cap, Spark colour is great nice tan brown
- Swapped CDI box with a spare,
-Timing is correct, perfect infact,
- Removed air box temporarily, and not at the same time- swapped exhaust, no difference,
-Compression is good (new piston rebore 400 miles ago)
-The gearbox smells of just gearbox oil (no petrol)- and not excessively smokey.


So now I only have two things to look at that I can think of, that being the reed valves(but would have to remove barrel to check),
or inspect primary ignition coils, and on reading up I found there are two primary coils, one has a reading of 193 ohms (and i have found that to be in spec with the haynes manual of 160-240).

The other coil is just 1 ohm however, which is likely the multimeter wires. So, a full ground to earth? I believe this coil is a 'high speed' coil, and resistence should read between 30-40ohms according to Haynes.

I'm fairly sure this is the problem, but I am just asking for clarification and possibly previous experience with other people?

As luck would have it my brother has the exact same bike, which also has the same problem of seemingly having this 'rev limit'. His (what I presume is the high speed coil) is 10 ohms, so also out of spec- So I can't swap stator to rule that out, unless I buy one.

The Haynes book being for almost every variation of the motorcycle from 79-89 is helpful to a point, but the above 'specification' resistences are for 'X' marked machines which mine is not.

Any advice/input guys?
Much appreciated.
____________________
CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S, 1979 MZ TS150.
Current: 1973 MZ ES250/2 - 18k, 1979 Suzuki TS185ER - 10k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 40k, 1989 MZ ETZ251 - 51k.

[jaffa90]

Have you tried giving it full throttle for a while and then switch off in neutral and then stop to smell the exhaust for petrol fumes and remove the spark plug to see if it`s also wet with fuel.

[blurredman]

I am tempted to remove the suspect coil, and see if the bike runs the same, if at all.
____________________
CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S, 1979 MZ TS150.
Current: 1973 MZ ES250/2 - 18k, 1979 Suzuki TS185ER - 10k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 40k, 1989 MZ ETZ251 - 51k.

[Nobby the Bastard]

Removing the coil won't hep, but having it re-wound will.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[blurredman]

[Steve_W]

I don't think I can really help, but I've got a very similar problem with an old GP100. Ticks over lovely, runs absolutely fine on lower revs but opening the throttle it just dies.

I've had carb cleaned by bike shop, cleaned air filter, replaced condenser, replaced ignition coil and plug cap, timing is spot on. I've even changed to a lower main jet as I thought that could be the issue. I have a spare stator (bought used from ebay so it may have the same issue if I'm unlucky I guess) and I'm planning on changing that this weekend.

I've not checked compression yet either, but I did check exhaust this weekend as well and that is not blocked from what I can tell.

The bike shop that cleaned my carb took it for a ride and said they think it's electrical and suggested changing stator - but me being me (lazy) I decided to try all the easier stuff first

Hope you get your issue sorted soon!

[blurredman]

Okay..

Stator testes were not successful. H/L speed coils tested out fine.

I swapped exhaust with my brother's motorcycle (exactly the same bike/model/capacity)..


Well well well. We have a conclusive result.. I swapped with my brother's exhaust pipe.. Guess what? bike started up first kick from cold (never done that before!), and ran well instantly. After a bit of a warm up up and down the lane I decided to put my jacket and lid on and head out on the public road a bit more.. Was a very different bike... Pretty much full rev range (it did lose puff about 6.5/7k but redline is only 8K. Got up to 55mph. Ran well..

Put each exhaust back onto their respective bikes, and mine takes the usual 3/4 kicks to start
____________________
CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S, 1979 MZ TS150.
Current: 1973 MZ ES250/2 - 18k, 1979 Suzuki TS185ER - 10k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 40k, 1989 MZ ETZ251 - 51k.

[Nobby the Bastard]

Take the exhaust off, chuck w load of petrol in it and set it on fire.

Once it's cold give it some decent taps to see if you can get some coke out of it.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Sister Sledge]

This ^^
A fire is always good anyway.

Some people use chemicals to clean them.
I had a 'snake' that I'd put into a power drill and shove through the exhaust to clean deposits out. The snake was some steel rope with thicker sized wires in it. On one end I tack welded it together which was the end for the drill chuck. The other end I bent the wires out into a sorta mushroom shape about the same diameter as the pipe fitting.
Reaming the wire through carefully (each end - make the wire just longer than half the pipe length) it was surprising how much coke was inside.

Not sure but did some of those exhausts come with a restrictor plate inside??
____________________
CCM 404 DS

[-]

Another good method it to bung up one end with something which wont get melted by caustic soda, stand it up against a wall and fill it.

I've done this with good results on my TDR.

If it has removable baffles, you might want to take these out too to see if there's any old knackered baffle material in there.
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TZR250 2MA road, TZR250 1KT road, TZR250 2MA race, TDR250, YZF-750R Boost colours.
Jaguar S Type 3.0 V6 Sport R, VW Transporter T5 GP LWB Shuttle 140ps DSG.