can't kickstart 500cr OR 430xc/cr

[scoott]

Got 430 xc together this weekend, new seals, piston& bore, mossbarger reed cage. Jetted waaay richer than anything else, with 38mm carb, like 450 main, 50 pilot , 6D needle one clip from top( may try full lean on needle. Motor runs hard with big surge on top, may cut head to get squish down to .40 from .72, but runs well as is....

Except it won't kickstart!!

Bump starts easily, hardly turns over before firing.

Tried different carb, advanced timing, ( good fat spark from internal ignition )

Think I'm cursed.

My 83 500 cr wouldn't kickstart untill I put a compression release in head that pops off when it fires. And I'm 6'3" and 220 lbs. No one else could start either.

Been all over the map with fresh crank seals, reeds, piston & bore, timing and ignitions ( internal rotor and external flywheel.) Oh, and different carbs and jetting.

Going to have to figure out how to rig up electric start at this rate.

Got my 83 250 xc back together with new seals, ignition retimed. Used to run like a sick 125, now it runs like an okay 125, oh well, at least it starts by kicking.

 

[Ron]

Scott,

I built a 79 390CR for my son about 2 months ago. I've tried to start it several times, cold and warm (6'1" 230 lbs 58yrs) but I can't start it.
My son (6'1" 210 lbs 28 yrs) gets on and fires it up every time. Difference is, he gives
it 2 or 3 hard "rapid" kicks (when cold). He starts it with one kick when its warm.
Guess why I ride a 77 250CR?
Ron

PS: You might try kicking it through 2 or 3 times holding the kill button with the throttle open to prime it.
I used that technique for cold starting a CR500 Honda, I had a few years ago.

 

[offyatindy]

Had the same problem with my '72 450 WR. Turned out to be the carb float. After messing with the standard, "set it so the fuel shuts off when level," I aimed it upward so it shuts off with a fuller bowl and the primer button can reach it and push it downward. Before, the bike (including newly rebuilt engine) took 10s of kicks to fire, if it would fire at all. Now it is a one kick starter.

 

[halffast]

scoott ,

I have to chuckle because my 84 CR500 has put me through the same misery ! Have you read the thread on here about starting the big bores ? I've tried about all the mods too , and she still doesn't want to start cold . Fresh bore and seals , Boysen reeds . smaller 38mm Mikuni , every jetting combo I can think of , different kicker , ground the kicker pall plate for more stroke , timing all up and down its range , fabbed a " Power Now " plate for the carb , installed a compression release in the cylinder ( ala 490 Maico ) , choke on - choke off , throttle open = throttle closed , I've blown into the carb vent tubes ( much to the amusement of my riding buddies ) , I've leaned the bike over to overflow the float bowl , I've rocked the bike back and forth in gear , I jumped up in the air to come down harder on the kicker , I've kicked until I almost passed out , and have cussed a blue streak........... all these efforts have done little to improve cold starting . It does start pretty well when warmed up now , though . As you stated , the bike will bump start so quickly it is ridiculous . Seems like the rear wheel doen't make a full revolution and it fires ! This bike RUNS and I would love to race it in some AHRMA events but I refuse to go to the line with this beast until I can hit on the magical , mysterious , fabled starting rituall that works . How in the H**L do the guys with the big bore autos get them started ? They can't be bump started can they ?

 

[Husq.fleet]

Put 250 primary gears in it. It speeds up the kicking which makes it start better. A good friend tried it with his 430 with awesome results. It will increase the kick effort a little, they aren't as high compression as the smaller bores. I took the pipe off of my miserable starting 83 500XC and watched the piston through a kick cycle, barely one stroke. We the slow kick the fuel isnt staying atomized which makes it harder to light. I took a barrel and piston out to a friend who I respect alot in the mixed gas world. He said the piston needed more ports/porting because it was covering up the ports causing it not to get a good draw into it. I never modded mine because I decided had no business on a 500. He spent alot of time with the Honda CR500 for both bikes and karting.

 

[White Husky]

You might try kicking it through 2 or 3 times holding the kill button with the throttle open to prime it.
I used that technique for cold starting a CR500 Honda, I had a few years ago.

That sounds like a good tip. I might try that myself!

PS - that bike you've built is gorgeous!

Kind regards
Lucien

 

[1Tuff500XC]

This should be sticky'd so others can be sure to spot this. I'd love more info/details on exactly what is needed. I will be getting into my '85 500XC project right at the first of the year, and also have an '88 510. Anything to make either bike easier to start, sounds great.

 

[fran...k.]

To the original poster, Scoott, Let's say you bump start it first thing in the morning, how much time or distance riding around does it take until it runs properly? Most all my bikes have taken quite a while perhaps at least a few tenths of a mile before running properly. I am talking about round slide micuni ones. Lately I have moved on to flat slide and crescent shaped slide carbs on two bikes and the one with the flat slide runs properly immediately or real close to immediately but lately doesn't seem start as reliably as I would like.

 

[scoott]

I

To the original poster, Scoott, Let's say you bump start it first thing in the morning, how much time or distance riding around does it take until it runs properly? Most all my bikes have taken quite a while perhaps at least a few tenths of a mile before running properly. I am talking about round slide micuni ones. Lately I have moved on to flat slide and crescent shaped slide carbs on two bikes and the one with the flat slide runs properly immediately or real close to immediately but lately doesn't seem start as reliably as I would like.

It takes awhile for it to clean out ( using a 38mm round slide) . Fought it this weekend, and then all of a sudden it starts twice in a row ( when warm) with one solid kick each time. Let it sit for an hour, fouls a plug.......

I have tried a 39mm pwk flatslide on my cr500. Didn't make any difference. Might try one on the 430.

My control is my 250xc, starts easily for everyone. Went from external to internal, still startys. Swap carbs, it starts with whatever, the big bores don't start with anything.

????????

I am getting closer though, the bike now pops once in awhile, and even kicked back once.

 

[Husq.fleet]

I have a Stewart Warner hand held shaft tachometer. Be curious of kicking speed difference between big bore makes, ones that start and ones that dont start easy. I think the compression ratio has alot to do with it also. Put tach on crank on ignition side, kick with no spark and check kicking speed. Should be easy enough for comparision. Also check small bores. Scoot my 84 250XC started so easy also as my 82 CR250.

 

[ruwfo]

Try this technique on your 500.

Turn gas & choke on, put bike in 3rd gear & rock the bike back & forth , to prime the cylinder, count to 30 . Turn Gas off & No choke, kick
the bike a good full kick ( always wear a MX boot). If the bike doesn't start in 2-3 kicks, put the bike in 2nd gear & roll bike backwards til it
stops. Put bike back in neutral & move kicker down about a 1/4 inch, stop, let kicker return to it's top position, now give it a healthy kick, should
start on the 1st kick.

By rolling the bike backwards in gear your bringing the piston to the top of the stroke, then by move the piston only slight with the kicker, your
starting the bike at it's highest stroke. This works either hot or cold. give it a try, you maybe surprised.

Husky John

 

[Ron]

Great info John, that sounds like a good idea for any bike.
Ron

 

['87 500XC]

Try this technique on your 500.

Turn gas & choke on, put bike in 3rd gear & rock the bike back & forth , to prime the cylinder, count to 30 . Turn Gas off & No choke, kick
the bike a good full kick ( always wear a MX boot). If the bike doesn't start in 2-3 kicks, put the bike in 2nd gear & roll bike backwards til it
stops. Put bike back in neutral & move kicker down about a 1/4 inch, stop, let kicker return to it's top position, now give it a healthy kick, should
start on the 1st kick.

By rolling the bike backwards in gear your bringing the piston to the top of the stroke, then by move the piston only slight with the kicker, your
starting the bike at it's highest stroke. This works either hot or cold. give it a try, you maybe surprised.

Husky John

You can do the same thing by kicking the bike slowly through with the kickstarter. It won't create a spark as it's not moving fast enough and it's quicker to do it this way. You can easily tell on any 2 stroke or 4 stroke when the motor comes up on compression (it's highest stroke as you call it, and on a 4 stroke the pistons highest stroke isn't always compression so the proper term to use is bring the bike up on compression not it's highest stroke) and once it does so let the kick starter return, engage and give it a kick. No need to actually put the bike in gear and rock back and forth.

And why exactly are we turning the gas off? Once proper fuel level is reached in the float bowl gas flow stops. It's a gravity system not force fed by a fuel pump. So unless you hold throttle open the level won't increase (or it shouldn't if the carb seals as it's supposed to). I've left my gas on by accident for two days once and my bike still started so again why are we turning the gas off?

And no choke? The ONLY reason why you would not need a choke on start up is if the bike was jetted too rich. For example, ALL huskys from the factory came so rich you didn't need choke to start it. If you are starting a bike with a cold motor with NO choke you are jetted to rich, period. Regardless if you left the gas on and "primed" the cylinder.

I'm sorry but I've been riding for a long time and I've never seen anyone do this or heard of this. It may have worked for you and you may think it's the proper way to start a bike cold but it just seems like a bunch of useless steps to get a bike started.

If a bike is setup properly the procedure for start is simple.

1. Gas on
2. Choke ON
3. Find compression (bigger the displacement the more important this is)
4. Kick (while kicking you may need to crack throttle to give a tad more fuel if the choke doesn't give enough, depends on the bike)
5. Rinse and repeat

No need to rock bike back and forth and with that procedure it rarely takes me more then 3 kicks to start a bike. I don't mean to come across as being snide but when I see this it makes me shake my head.

 

['87 500XC]

And to the original poster of thist thread scoott. You mention you are way richer than anything else. You think this can be your issue???? Way rich doesn't mean it'll start easier, sometimes a bike won't start at all if it's too rich.

 

[ruwfo]

Well, the method works on my Husky 510, 500. 430 & 390, I don’t use it for my 125 & 250’s as they usually start the normal way, as you put it. I’ve been riding for 30+ years & have seen guys lay the big bore bikes on there sides to prime the carb? To get them started.

Whatever works , & this works for my big bore Huskys for the past 5-6 racing season (when I returned to MX) & I’ll continue to use it til it don’t.

I don’t agree with opening the throttle though when start a bike unless it flooded.

Here’s a Super Hunky article on why NOT to open the throttle while trying to start your bike.

DON’T OPEN THAT THROTTLE WHEN USING THE CHOKE!
Air flowing into the starting carburetor makes fuel come out of the bowl to join the airflow, and this is caused by the high vacuum, or suction, because you are cranking the engine. The piston is moving up and down gasping for air, but it can’t get very much, so vacuum is high.
What makes high vacuum behind the throttle slide, is the fact that you are cranking the engine with theTHROTTLE SLIDE CLOSED. Leave the throttle completely closed until the engine starts. If you can’t resist opening the throttle with a spastic reaction every time your kicking foot moves down, try putting your right thumb in your mouth.
If you insist on opening the throttle, the vacuum behind it disappears and the starting carb will not work. Most of the hard starting of Mikuni-equipped bikes is caused by this right-hand syndrome

http://articles.superhunky.com/4/55

Husky John

 

['87 500XC]

Well, the method works on my Husky 510, 500. 430 & 390, I don’t use it for my 125 & 250’s as they usually start the normal way, as you put it. I’ve been riding for 30+ years & have seen guys lay the big bore bikes on there sides to prime the carb? To get them started.

Whatever works , & this works for my big bore Huskys for the past 5-6 racing season (when I returned to MX) & I’ll continue to use it til it don’t.

I don’t agree with opening the throttle though when start a bike unless it flooded.

Here’s a Super Hunky article on why NOT to open the throttle while trying to start your bike.

DON’T OPEN THAT THROTTLE WHEN USING THE CHOKE!
Air flowing into the starting carburetor makes fuel come out of the bowl to join the airflow, and this is caused by the high vacuum, or suction, because you are cranking the engine. The piston is moving up and down gasping for air, but it can’t get very much, so vacuum is high.
What makes high vacuum behind the throttle slide, is the fact that you are cranking the engine with theTHROTTLE SLIDE CLOSED. Leave the throttle completely closed until the engine starts. If you can’t resist opening the throttle with a spastic reaction every time your kicking foot moves down, try putting your right thumb in your mouth.
If you insist on opening the throttle, the vacuum behind it disappears and the starting carb will not work. Most of the hard starting of Mikuni-equipped bikes is caused by this right-hand syndrome

http://articles.superhunky.com/4/55

Husky John

So we went from rocking the bike back and forth the laying the bike on its side. Ok well in that case yes laying the bike over can help but that's not was I was reffering to.

And as far as throttle goes nothing is set in stone. My KTM 200 refuses to start with throttle open so I don't bother, my dads KTM 380 needs a bit of throttle or it won't start. And I remember way back when I had a KX 100 it needed a bit of throttle to start which was why when I got the 200 I had such a hard time starting it as I was used to giving it a bit of throttle. So again, just because an article said it's not a good idea doesn't mean it's set in stone. Now the KTM's have Keihin carbs and the husky has a Mikuni. So that's why I specifically said "depends on the bike".

In the end yes, whatever works for the person doing the task. My only point is that by kicking the bike through with the kick starter is the exact same thing as rocking the bike until it finds compression.

And I still don't agree with turning the fuel off and turning the choke off and I will stick to my guns saying if you need no choke to start a cold bike you are too rich.

 

[Husq.fleet]

The 430 in the pic starts like this. Cold, turn gas on, kick slowly through a couple of times while finding top dead center. Rock kicker to find very top. Turn choke on and kick fast, usually starts first kick. I judge my pilot jet by how long I have to run the engine with the choke on. I like to have the choke basically just on to enrich it enough to fire. 10-20 seconds choke off and keep it running with throttle. Choke on for a long time to keep it running, too lean of pilot and vice-versa.
Or you can try this method. Cold engine, gas on, spray starting fluid into air filter with throttle partway open, choke on, kick like always and if it fires right up your starting issue is fuel related. Bultaco mechanic showed my dad and I that in the early 70's.

 

['87 500XC]

The 430 in the pic starts like this. Cold, turn gas on, kick slowly through a couple of times while finding top dead center. Rock kicker to find very top. Turn choke on and kick fast, usually starts first kick. I judge my pilot jet by how long I have to run the engine with the choke on. I like to have the choke basically just on to enrich it enough to fire. 10-20 seconds choke off and keep it running with throttle. Choke on for a long time to keep it running, too lean of pilot and vice-versa.
Or you can try this method. Cold engine, gas on, spray starting fluid into air filter with throttle partway open, choke on, kick like always and if it fires right up your starting issue is fuel related. Bultaco mechanic showed my dad and I that in the early 70's.

Atleast someone knows how to start a big bore.

Half the people out there shouldn't even own one as they can't start them. You have to kick them like a viking, there's no black magic and all bikes are started the same way especially tow strokes.

Oh and forgot to add that the old rocking back and forth thing was from the days of bing carbs with the tickler instead of a choke in the 70s (which on a 2 stroke isn't a choke, it's an enrichment port that opens up). But anyways all the rocking did was charge the lower end of the motor. This is not needed on these bikes of this vintage. Just another statement to show that the rocking back and forth trick is useless. Find top dead with the kickstart, and kick like you mean it.

 

[endurokids]

I just finished my '84 430 WR and it only starts when the piston is at the top, and the kickstart lever is aligned with the top of the shock. (the highest point it will reach when putting pressure on the kickstarter) Kick like you are mad at it. I'm using the straight kickstart lever, not the "S" looking one for more leverage.
Then she starts on the first or second kick every time.

 

['87 500XC]

I just finished my '84 430 WR and it only starts when the piston is at the top, and the kickstart lever is aligned with the top of the shock. (the highest point it will reach when putting pressure on the kickstarter) Kick like you are mad at it. I'm using the straight kickstart lever, not the "S" looking one for more leverage.
Then she starts on the first or second kick every time.

The "S" looking one or pretzel logic one was actually a bad design. It didn't really give you more leverage per say, it did however put more torsional load on the kick starter shaft as the area where you rest your foot was further away from the bike. Kick starter shafts have broken off with that style kick starter so stick with the normal one.