Kick Back

[nellyp]

My Honda Sonic has been kicking back every now and again since I had the Engine rebuilt. I thought it would disappear as it was being run in but it hasn't. What would be the main cause? I would have thought timing but, but how would you check that on a Sonic? Also could it be anything else? By the way it will do it when hot or cold

[submaniac]

What do you mean by "kickback"? Like an explosion sound from the exhaust? If it is that, then the cause is too much unburned fuel getting into the exhaust. In other words, your fuel mixture is too rich. It happened on my (POS) Harley, and it was the carbs that were the problem.

[Semper]

Also could it be anything else

You have to be more committed when you kick it. A slow/no power when kicking wil normally get you a "kick back". You should be lucky that it's only a 125 Sonic.

Edited February 1, 2012 by Semper

[nellyp]

What do you mean by "kickback"? Like an explosion sound from the exhaust? If it is that, then the cause is too much unburned fuel getting into the exhaust. In other words, your fuel mixture is too rich. It happened on my (POS) Harley, and it was the carbs that were the problem.

A kickback is when you use the kick start and it bounces back at you like a bullet

[nellyp]

Also could it be anything else

You have to be more committed when you kick it. A slow/no power when kicking wil normally get you a "kick back". You should be lucky that it's only a 125 Sonic.

I remember back in the 80s having 175 185 and 250 2 strokes that never gave me the problem when I was kicking them over. I'll try to be a bit more committed to the bike but my misses might not like it

[smedly]

kick back as you call it is where the single piston engine momentarily fires in reverse, there may be a problem with the kickstart mechanism or you are not giving it the full downward kick, I remember an old BSA off road single cylinder 650cc trial bike that would actually start up in reverse the odd time and the kick back if it happened could break your leg, first bike I ever rode and it was scary at 13yoa

[barefoot1988]

most likely you arent used to the new compression and arent kicking it fully down. i got 2 tiny stitches from starting my old ktm egs lol

[Timthai]

You have had the engine rebuilt so you now have full compression.

If you try to start it when the piston is at the bottom of its stroke, you are not getting a full compression stroke and it will kick back against the compression before it gets past the top of the stroke and fires.

When you start it, push the kick start down a couple of times gently till you feel that it's past the ports and you have compression, then let it back up and kick it from there. That way you are sure to it will get past the top of the stroke and fire. (with full compression,

Cheers.

[karlos]

You have had the engine rebuilt so you now have full compression.

If you try to start it when the piston is at the bottom of its stroke, you are not getting a full compression stroke and it will kick back against the compression before it gets past the top of the stroke and fires.

When you start it, push the kick start down a couple of times gently till you feel that it's past the ports and you have compression, then let it back up and kick it from there. That way you are sure to it will get past the top of the stroke and fire. (with full compression,

Cheers.

Exactly what this guy said

[Beardog]

kick back as you call it is where the single piston engine momentarily fires in reverse, there may be a problem with the kickstart mechanism or you are not giving it the full downward kick, I remember an old BSA off road single cylinder 650cc trial bike that would actually start up in reverse the odd time and the kick back if it happened could break your leg, first bike I ever rode and it was scary at 13yoa

Yea I know how Bsa's are My buddy had a 500 BSA he used for mountain climbing(What a beast)

At least it has a decompression lever so you didn't bust your foot into shards.

[transam]

Valve timing out (chain) or they've swopped in a BSA Gold star Lump.

[xen]

Many Years ago , i had a Norton ES2 , (a 500 single ) and that had a lever on the handle bar to advance or retard the spark when starting. This was to prevent kickback but i can't remember if it was advance or retard so it wouldn't kickback. It also had a compresion release lever on the handle bar too but this was disabled when i bought it. The compresion release would open a valve to let a bit of the compresion out) so what I had to do is stradle the bike , kick it into gear and pull the bike backwards to get it off TDC (Top Dead Centre) otherwise i could not get the kickstart to move no matter how much i jumped on it. You could always feel it in the kickstart when the piston was on the way down because it would be an easier kick .

I bought this bike cheap because it had broken the previous owners leg ,and apperently a few other too . It gave me the hobbles a few times too but i always wore big heavy motorcycle boots when starting it. But what i am getting to is perhaps you need to get the bike of TDC before you kick it .

[ClareQuilty]

I hesitate to reply as I have no solution for you, but since others have shared their stories of 'kickback' or kick-start levers kicking back I will too, as the bike that did it to me was more similar to yours.

I once had a new Honda Wave 125 I was talked into purchasing about six years ago and the thing was horrible for kicking back when you tried to kick start it - it was like the cylinder was always in the wrong place in its stroke for kickstarting, no matter what. Its funny because other Waves I've driven were not like that, and most other small engine bikes are not, whether four or two stroke.

That bike had several other problems - difficult to start in cold weather, a few little rough edges on various plastic parts that actually cut my hands - and it ended up absolutely turning me against Waves and generally leading me to favor the three other brands now nearly run out of business in Thailand.

Btw, just an edit to add an admittedly sexist comment... have you guys ever watched a foreign woman try to kick start a motorbike?

Edited February 1, 2012 by ClareQuilty

[nellyp]

Thank you all for the advice. It seems that I will have to start pouting more effort into the kick. I will try it for a week and let you know how it goes.

[transam]

Thank you all for the advice. It seems that I will have to start pouting more effort into the kick. I will try it for a week and let you know how it goes.

When it starts has it the same performance or does it feel less powerful ?

[billd766]

The old Arial square 4 and Vincent 1,000 cc had a compression relief valve lifter but if you got it wrong it could easily throw you off the bike and do some serious damage to your body.

The Arial square 4 was a collection of vibrating nuts and bolts only held closely enough together to allow the oil to leak out.

[nellyp]

Thank you all for the advice. It seems that I will have to start pouting more effort into the kick. I will try it for a week and let you know how it goes.

When it starts has it the same performance or does it feel less powerful ?

I'd say that the performance is about the same. Though I don't know if the power is up to scratch anyway. I can clock about 120km/h on her but all of that is done revving it up the gears till 4th. Once I hit forth the acceleration is gone and the speed slowly goes down to about 85-90km/h even with the throttle all the way open. I have been led to believe that is because 5th is a cruising gear

Cheers

[transam]

Thank you all for the advice. It seems that I will have to start pouting more effort into the kick. I will try it for a week and let you know how it goes.

When it starts has it the same performance or does it feel less powerful ?

I'd say that the performance is about the same. Though I don't know if the power is up to scratch anyway. I can clock about 120km/h on her but all of that is done revving it up the gears till 4th. Once I hit forth the acceleration is gone and the speed slowly goes down to about 85-90km/h even with the throttle all the way open. I have been led to believe that is because 5th is a cruising gear

Cheers

If you bike has a chain crank/cam drive it could be a tooth out.

[nellyp]

Thank you all for the advice. It seems that I will have to start pouting more effort into the kick. I will try it for a week and let you know how it goes.

When it starts has it the same performance or does it feel less powerful ?

I'd say that the performance is about the same. Though I don't know if the power is up to scratch anyway. I can clock about 120km/h on her but all of that is done revving it up the gears till 4th. Once I hit forth the acceleration is gone and the speed slowly goes down to about 85-90km/h even with the throttle all the way open. I have been led to believe that is because 5th is a cruising gear

Cheers

If you bike has a chain crank/cam drive it could be a tooth out.

Interesting. How would I check that?

[transam]

Usually the chain cogs have marks to line up somewhere but l have no idea about your rides setup.

[Semper]

Turn the crank to TDC, then check the marking on the camsprocket. It should align with a marking on the cylinder head.

[nellyp]

Turn the crank to TDC, then check the marking on the camsprocket. It should align with a marking on the cylinder head.

Top dead centre I can do but I don't know where the cam sprocket is. it's shit not having a manual

[transam]

Turn the crank to TDC, then check the marking on the camsprocket. It should align with a marking on the cylinder head.

Top dead centre I can do but I don't know where the cam sprocket is. it's shit not having a manual

You will definitely need a manual or perhaps on the Net to find the correct alinement points, engines are not all the same.

[MaiChai]

Assuming you paid for the engine rebuild, you should take the bike back and ask them to check the cam chain is properly aligned. They may have got distracted while assembling it!

I have replaced the chain on a Smash and Wave before and there are marks that help you alighn everything up. Sometimes its a tooth out and you use something like a small allen key to lift the chain off the cam and move it a tooth either side. When checking you need to make sure you turn the engine over the right way and the tightness on the cam chain is in the right direction. Single piston engines are pretty easy to workout how to setup (I never used a manual with a Wave or the Smash) although anything more complex definitely needs a shop manual! Needless to say the clever money makes a note of the alignment before disassembly, especially if you dont have a manual!

Edited February 4, 2012 by MaiChai