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DougieB 2 Mar 2006 18:50

starting lumpy singles
 
After leaving my TT600RE for a few weeks, it takes ages to start (lecce starter). Why? What's the technical explanation?

I know it's a comming big single feature, but I just wondered why. The old Enfield I had, 500cc single, started first kick every time. So what's the difference, if we're talking general terms?

cheers,

leigh 3 Mar 2006 00:13

Two reasons, firstly, the headlights are wired on permanently so precious juice is going to the 55 watt headlight instead of the spark plug. TT600Rs are difficult to start if you kick them over with the lights switched on. Secondly, they have a "female" quality about them, i.e. they will only get going when they feel like it! If it wont play ball a dash of easy start in the airbox should fire her up.

DougieB 3 Mar 2006 14:29

"they have a "female" quality about them"

just the kind of technical reasoning I was look for http://www.horizonsunlimited.com/ubb/smile.gif

I've seen a similar thing with a Dommie, always started but after a lots of attempts. I'm going to put in a switch for the headlight, it's rubbish anyway better off with a candle!

Does it have anything to do with piston speed? As in, when I kick started the Enfield I was able to generate mucho speed in the piston and this in turn compressed the mixture wll making it easier to burn/ignite. Whereas the TT (Dommie, XT, etc) have higher compression engines and therefore require more power (which the starter struggles to provide) to work the piston up to a speed to get that compression. In addition the weak sparking only makes the ignition more difficult. And by spraying some easy start in you're making the mixture easier to ignite when it's 'under compressed'.

Or is that just rubbish?

JonStobbs 3 Mar 2006 14:41

Try turning on the petrol tap a few moments before you go to start it,works for my XL600.Seems to be the petrol that was in the float bowl when you last used it has mostly evaporated,and just needs time to refill.It probably does'nt seem so much of a problem with multis as there's a lot less work for the poor old starter motor to do,so it'll spin over faster.
Would'nt really start using Easy Start unless it's in a dire emergency,as it disolves the carbon that has built up in the cylinder head and around to top of the bore which actually helps the compression a little.There is an old farmer's tale that says if you start using Easy Start on an engine,you'll have to keep on using it as the motor will become "addicted" to the stuff! Don't know about that though it does smell quite nice....


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Just going for a short ride on my bike....

Mark 3 Mar 2006 17:40

Another possibility is that the more volatile element of the fuel in the float bowl has evaporated, leaving only the harder to ignite part to start the engine.

There have been ocasions when I have left a bike for a couple of months, or less and have failed to get start it on the kick start despite 5 minutes of huffing and puffing. I have then drained the float bowl, but not the tank, let the carp re-fill and it has fired up ofter 1 or 2 kicks!

This can easily be avoided by turning the the petrol tank tap off a couple of minutes before you get home if there is a chance you won't be using the bike for a while.

I would also try unplugging the headligh bulb when trying to start to see if it appears to help, unless the ignition system is CDI, which doesn't use the battery to produce sparks, unlike TCI electronic ignition

Good luck

Mark

Shells 3 Mar 2006 20:27

Dougie,
I just spent the morning out in the cold trying to start my Dommie and can fully testify to my bike's .. ahem.. personality http://www.horizonsunlimited.com/ubb/smile.gif
Got her going though, and now just need to give her some luvvin (doesn't like being outside in the cold alone for too long)

I have had several answers to the question of starting my single after I have left her outside in the cold for a few weeks. I'm not sure there is a technical answer. Make sure you get that switch done for the headlight, consider a battery charger if she has to stand for long periods, and then it's just a battle of wills!

I have had some excellent help from http://cres1.lancs.ac.uk/~esarie/honda/techbrd.htm - a technical help board (some excellent Honda based knowledge). Something in there may be a solution to the single starting problem?

leigh 5 Mar 2006 22:26

I have experimented this frosty weekend on my two identical TT600REs, drained and refilled the float bowl on one and not the other. The drained/ refilled one started straight away, the other nearly killed off the battery trying to start until I gave it the same treatment. Fresh petrol must be better!

DougieB 3 Apr 2006 22:25

just got my bike out after leaving it sitting for a few weeks. Emptied the carb of the old fuel and it started first push of the button. It normally almost drains the battery trying to start... Duff fuel seems to cause the starting problems.


cheers,
Doug

Matt Roach 4 Apr 2006 00:19

Dougy,

Maybe it was just those massive quadriceps of yours that made starting the Enfield so easy! I have similar starting problems with my 640 Adventure after it has been out of action for a while, so I feel your pain!

winmac 4 Apr 2006 04:56

I've also noticed that gasoline goes stale much easier than it used to, they must have removed some of the additives. At on time you could leave gas in a old tractor you might use once a year for rakeing hay and it would fire up and at least run on it. now if you leave gas it turns to sludge in no time.


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