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-   -   1984 xt600 kicks back--HELP!!! (https://www.horizonsunlimited.com/hubb/yamaha-tech/1984-xt600-kicks-back-help-60081)

Spyder1427 7 Nov 2011 17:15

1984 xt600 kicks back--HELP!!!
 
Hi,
I bought an 84 xt 600 not running.
Cleaned out the carbs and installed new compression release cable.
Also the kick start stop was broken. replaced those and put and new gear on the start shaft. bushing was loose.

Now it starts.
But it kick back so badly it felt like it broke my ankle.

What did I do wrong?

Thank you very much in advance for any help.
Josh

chucky55 7 Nov 2011 20:35

Big secret to start xt
 
Spyder,

Do not use any throttle when starting, choke only, do not use throttle.

Did I mention-DO NOT USE THROTTLE,
my method, apply choke, grab throttle , twist forward(NO throttle) grab front brake, KICK.

Cheers from Oz.

Walkabout 7 Nov 2011 20:46

Quote:

Originally Posted by Spyder1427 (Post 355105)
Hi,

But it kick back so badly it felt like it broke my ankle.

What did I do wrong?
Josh

Nothing! It is all part of the character of a kicker :thumbup1:

Mind you, it is probably worth checking the timing.

Also it is good character building stuff to own a bike with a kick start!!

backofbeyond 8 Nov 2011 07:49

There's a technique to kick starting big singles. First, as Chucky said, no throttle. Do the kicking bit with the throttle shut.

For the next bit I'm assuming you've got the timing right and that it's not stuck / defaulted to full advance. The timing for starting should be around 5-10 degrees BTDC. If it isn't, for whatever reason, it will kick back. It's unusual for modern(ish) Jap stuff to have a timing problem but for the sake of your leg it's worth checking.

Next you need to get the piston in the right place for starting - slowly push the kickstarter down until you can feel it come up on the compression stroke. Now pull in the compression release and ease the piston just past the top of its stroke (you can feel it move). Release everything, let the kickstart come back to the top and come down on it with your whole weight. You need to get the piston moving as quickly as you can - a wimpy kick won't work. Keep the throttle shut!

The idea behind getting the piston just past TDC before kicking is that it then has two complete revolutions to get some speed / momentum going before the firing stroke (and at the same time the kickstart reaches the bottom of its stroke and disengages from the engine, so saving your leg). Half strength kicking or starting with the piston in the wrong place are the main causes of kickback.

If it doesn't start within 2-3 kicks you've probably flooded it. Switch off ignition, switch off fuel and choke, open throttle fully with compression release pulled in and kick the engine over 3-4 times to remove excess fuel. Then switch everything back on and start again.

Spyder1427 8 Nov 2011 19:34

I have now been through pretty much the whole bike's electrical system.

we removed the stator and pickup coil. tested pickup coil with ohm meter and it was out of spec by 100 ohms. we froze it and heated it. now there it has an open loop in it.

I am trying to find a replacement now.

Could this be the reason it kicks back? Is it getting a signal to fire to early?

It is kicking back enough to throw a 250lb person over the bike.

thank you again for any input.
Josh

wetcoastrider 9 Nov 2011 08:59

sounds familiar.
 
I had my 83 xt550 do the same thing to me that resulted in a fractured tib, turned out to be the pickup coil as you have already figured out. I found a replacement stator on ebay for around a 100 bucks but that was kind of lucky i think.

unfortunately the pickup is just part of the stator and you usually have to replace the whole thing. I looked into buying an aftermarket pickup coil and attempting to rewire and squeeze it in there but since nothing I could find looked remotely close to the right size i just opted for the ebay option.

or if you want to go new be prepared to shell out.
1984 XT600L Yamaha Motorcycle GENERATOR Diagram and Parts

potentially you could find someone in your area that does rewinds but also expensive and the pickup is quite 'packaged' making it more difficult.

maybe this one will do.http://www.ebay.com/itm/XT600-84-89-STATOR-COIL-MAGNETO-GENERATOR-ALTERNATOR-86-/130531711803?pt=Motorcycles_Parts_Accessories&vxp= mtr&hash=item1e644bdb3b


I would email the seller and ask for the ohm reading across the coils to confirm they are within spec.


I just swapped mine over and absolutely no kickbacks since

also, starting procedure mentioned above makes everything safer too.

good luck

Fasteddie956 3 Feb 2016 02:45

Hi my name is Eddie. I have same problem with same bike. 1984 Yamaha xt600. I bought it used. It did start when I bought it but I didn't have it long before the nasty and severe kick back occurred with me too. I had the carbs cleaned and it didn't matter. I'm thinking after reading all the posts it might be a stator coil? Is a 1983 model the same?
Could it also be a decompression cable or timing? I only paid 600.00 for the bike and don't want to waste money on guessing. What is the most common reason stator? If so is there a easy way to test it to know if the one that's in the bike now is bad?
Thanks everyone in advance for possible help with my near foot breaking problem.
Sincerely Eddie

Lowrider1263 3 Feb 2016 15:48

On the decompression cable there is a adjuster down the cable near the engine with the engine at top dead centre try pulling on the cable to see how much play you have coming from the engine side.
The amount of play should only be a millimetre, if you have to much play then you will find when you kick down it will jam on the way down on occasions as the decompression is not happening at the right time.
I can start my xt kicking it down using my hand.
The starting point of the kick is the last quarter of the kick the first three quarters is to get momentum.

Lowrider1263 3 Feb 2016 15:55

Quote:

Originally Posted by backofbeyond (Post 355181)
There's a technique to kick starting big singles. First, as Chucky said, no throttle. Do the kicking bit with the throttle shut.

For the next bit I'm assuming you've got the timing right and that it's not stuck / defaulted to full advance. The timing for starting should be around 5-10 degrees BTDC. If it isn't, for whatever reason, it will kick back. It's unusual for modern(ish) Jap stuff to have a timing problem but for the sake of your leg it's worth checking.

Next you need to get the piston in the right place for starting - slowly push the kickstarter down until you can feel it come up on the compression stroke. Now pull in the compression release and ease the piston just past the top of its stroke (you can feel it move). Release everything, let the kickstart come back to the top and come down on it with your whole weight. You need to get the piston moving as quickly as you can - a wimpy kick won't work. Keep the throttle shut!

The idea behind getting the piston just past TDC before kicking is that it then has two complete revolutions to get some speed / momentum going before the firing stroke (and at the same time the kickstart reaches the bottom of its stroke and disengages from the engine, so saving your leg). Half strength kicking or starting with the piston in the wrong place are the main causes of kickback.

If it doesn't start within 2-3 kicks you've probably flooded it. Switch off ignition, switch off fuel and choke, open throttle fully with compression release pulled in and kick the engine over 3-4 times to remove excess fuel. Then switch everything back on and start again.

On the xt 500 they had a decompression lever on the handle bar you pulled in to get the stroke to top dead centre, on the xt600 they didn't

steveloomis 3 Feb 2016 16:09

The method I use relies on the automatic decompression properly adjusted and working.

Slowly kick until you hear a loud (rather loud) click, stop, allow kicker to return to top then with throttle closed kick very hard and fast. Use choke if engine is cold. Once you hear it fire add a little throttle to keep it running. :funmeteryes:

The click you hear is the decompression lever, you can see it move when it clicks.

Fasteddie956 3 Feb 2016 18:29

Hi guys Eddie here again. Thanks so much for your time and kindness in replying to my requests for help. I had a 1984 XL600R that had tough to kick lever compression but it never ever came back to almost literally break my foot in the instep. I don't remember hearing a "click" when I try finding top dead center with the kick start lever. Maybe it's a combination of the auto decompression cable and a defaulted stator?
I have to drop the bike off to a private all around mechanic who is the son of a friend. I just want to know what possible things could be causing this so I can tell him what you guys suggested and what parts to buy from ebay.
Lastly does anyone know if a stator assembly from a 1983 xt600 will work on the 84 model?
I'm going to try all the things you guys are suggesting. One post said they replaced the stator assembly and it corrected the problem. Is there a way to check if it's in spec as far as ohm. I'm a little confused how it all works. Any to make matters worse the local yamaha dealers won't even take it in as a repair job because it's so old they say they don't want to get involved. Thanks everyone for much needed advice. Let me know all the steps I should cover. I'll check the decompression cable too.
Eddie

Lowrider1263 3 Feb 2016 18:41

Quote:

Originally Posted by Fasteddie956 (Post 529119)
Hi guys Eddie here again. Thanks so much for your time and kindness in replying to my requests for help. I had a 1984 XL600R that had tough to kick lever compression but it never ever came back to almost literally break my foot in the instep. I don't remember hearing a "click" when I try finding top dead center with the kick start lever. Maybe it's a combination of the auto decompression cable and a defaulted stator?
I have to drop the bike off to a private all around mechanic who is the son of a friend. I just want to know what possible things could be causing this so I can tell him what you guys suggested and what parts to buy from ebay.
Lastly does anyone know if a stator assembly from a 1983 xt600 will work on the 84 model?
I'm going to try all the things you guys are suggesting. One post said they replaced the stator assembly and it corrected the problem. Is there a way to check if it's in spec as far as ohm. I'm a little confused how it all works. Any to make matters worse the local yamaha dealers won't even take it in as a repair job because it's so old they say they don't want to get involved. Thanks everyone for much needed advice. Let me know all the steps I should cover. I'll check the decompression cable too.
Eddie

In the dealership unless it's got a plug so they can plug a diagnostics unit in they are not sure how to diagnose a problem,
The machanics are still in there nappies, I've got bikes older than them

pete j 4 Feb 2016 10:14

Hi Eddie,

XT 600s don't kick back. Spark timing must be wrong. We had that here after a stator rebuild.
There are 2 pick-ups for timing, one for slow and one for fast. 3 wires come from pick-up: green is common, white with green and white with red go to CDI.
Can't find the note i made to self which is which. Quite possible to get those mixed up, try swopping the 2 white with green/red trace.

Best.
p

bolla 4 Feb 2016 20:29

Throttle needs to be kept shut while starting
Even if the throttle is fully closed the throttle stop screw on the carb may be screwed in a bit to much, this has the same effect as opening the throttle.
I would try unscrewing the throttle stop.

Fasteddie956 5 Feb 2016 01:57

Thanks fellas for the help!!! BTW where is the throttle stop screw located? And I'll check the wires too for the stator pick up. Thank you guys so very much


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