Yamaha Thundercats
Would you like to react to this message? Create an account in a few clicks or log in to continue.

trouble starting from cold

+2
yamahamad
Panthro
6 posters

Go down

trouble starting from cold Empty trouble starting from cold

Post  Panthro Wed Apr 13 2011, 09:41

Got the cat back from the garage last week after having work on cleaning out the carbs.
Apparently some o'rings were replaced and debris removed, and the bike certainly feels smooth and pulls very fast, no flat spots etc.

However, every morning since ive had it back its been a nightmare to start.
At first I just thought I didnt have 'the knack' to starting this bike (only had it a couple weeks) but now ive had a few morning efforts in a row it seems no matter what I try its stubborn to fire up.

The starter motor winds fine, and the battery is strong, its also had new plugs last week, but its just keeps turning over with no joy.
If I apply any choke at all I can smell fuel and the problem seems worse.
Then I leave the bike for a few minutes and usually it fires up. Interestingly it seems to require no choke from start up and rides smooth immediately.
When warm it ticks over at around 1400rpm.

Also(weirdly), it seems to start fine when leaving work, after 8/9 hours of standing, but only causes me problems when firing up in the morning.

Initially I thought it was classic flooding symptoms but even with zero throttle and no choke im having the same problem. Could the carbs be letting fuel by when standing? Or am I overlooking something simple?
Shouldnt choke be required from cold?
Im going to consult the garage I had it in last week, but wanted a bit more ammunition before he tries to fob me off..
Panthro
Panthro
3Bronze
3Bronze

Male Status :
Online
Offline

Number of posts : 26
Humour : love me, love Gervais
Registration date : 2011-03-13


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  yamahamad Wed Apr 13 2011, 12:53

It is possible that 1 or more carbs are leaking fuel into the cylinder(s) but usually you would get hydrolock where the engine will not turn over fast or not at all. Possibly the air/fuel mixtures are not correct but as you say it runs very well otherwise. I would suggest speaking to the people who did the carb work about the problems.
You would normally need full choke to start on a cold morning but no choke at all on a warm day unless stood for more than a few hours.
Paul.
yamahamad
yamahamad
6Gold
6Gold

Male Status :
Online
Offline

Number of posts : 2002
Hobbies : Bmw technician. Weight training. Music. Beer.
Humour : big american 4x4?
Registration date : 2009-11-16


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  weasley Wed Apr 13 2011, 13:48

Start sequence on mine:

- turn key and listen for the fuel pump priming - wait until stopped
- full choke
- no throttle
- push button

It'll usually fire at this point and I usually have to then use a really little bit of throttle to keep it alive. It'll then run at a fast idle without throttle - I then faff about putting my earplugs, helmet, gloves etc on, gradually backing off the choke to maintain a fast idle. By the time I'm ready to ride, I can put the choke in and it'll rev cleanly.

If it doesn't catch first time it can take a few attempts to start after that, usually if it has been stood for a while.
weasley
weasley
Admin2
Admin2

Male Status :
Online
Offline

Number of posts : 1506
Hobbies : Yes
Humour : Yes
Registration date : 2008-11-07


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  Rosco Wed Apr 13 2011, 18:53

weasley wrote:Start sequence on mine:

- turn key and listen for the fuel pump priming - wait until stopped
- full choke
- no throttle
- push button

It'll usually fire at this point and I usually have to then use a really little bit of throttle to keep it alive. It'll then run at a fast idle without throttle - I then faff about putting my earplugs, helmet, gloves etc on, gradually backing off the choke to maintain a fast idle. By the time I'm ready to ride, I can put the choke in and it'll rev cleanly.

If it doesn't catch first time it can take a few attempts to start after that, usually if it has been stood for a while.

+1
Rosco
Rosco
Admin2
Admin2

Male Status :
Online
Offline

Number of posts : 6662
Humour : Oh Go On Then
Registration date : 2008-11-06


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  Panzerbuilder Wed Apr 13 2011, 18:59

Rosco wrote:
weasley wrote:Start sequence on mine:

- turn key and listen for the fuel pump priming - wait until stopped
- full choke
- no throttle
- push button

It'll usually fire at this point and I usually have to then use a really little bit of throttle to keep it alive. It'll then run at a fast idle without throttle - I then faff about putting my earplugs, helmet, gloves etc on, gradually backing off the choke to maintain a fast idle. By the time I'm ready to ride, I can put the choke in and it'll rev cleanly.

If it doesn't catch first time it can take a few attempts to start after that, usually if it has been stood for a while.

+1

+2
Panzerbuilder
Panzerbuilder
4Gold
4Gold

Male Status :
Online
Offline

Number of posts : 1221
Humour : Anything that puts a smile on my face ;-)
Registration date : 2010-03-04


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  SteveCat Wed Apr 13 2011, 21:43

weasley wrote:
- turn key and listen for the fuel pump priming - wait until stopped
- full choke
- no throttle
- push button

The norm for mine too, but I have had times where it will refuse to fire up (at any temp). Turn the key back to off and start from 'beginning' again allowing for a 'flooded' engine and all is fine. In my case something isn't 100% with the ignition switch (or the numpty operator who can't turn it properly Twisted Evil )

There's a couple of issues you've mentioned in the past, might be worth arranging a meet at Ryka's or Newlands and we can compare notes, even maybe taking a ride in some of Surrey's finest or invade a neighbouring county or two Very Happy
SteveCat
SteveCat
Admin2
Admin2

Male Status :
Online
Offline

Number of posts : 5110
Humour : You've gotta be joking
Registration date : 2008-11-06


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  Panthro Wed Apr 13 2011, 21:52

I agree with the above starting sequence, my previous cat was just the same.

I called my mechanic today and he agreed that there sounds to be fuel leaking through into at least one cylinder when the bike is sat.
He has offered to take the bike in on monday and check it out, so ill let you know how it goes.
Panthro
Panthro
3Bronze
3Bronze

Male Status :
Online
Offline

Number of posts : 26
Humour : love me, love Gervais
Registration date : 2011-03-13


Back to top Go down

trouble starting from cold Empty Re: trouble starting from cold

Post  Panthro Wed Apr 13 2011, 21:54

SteveCat wrote:
There's a couple of issues you've mentioned in the past, might be worth arranging a meet at Ryka's or Newlands and we can compare notes, even maybe taking a ride in some of Surrey's finest or invade a neighbouring county or two Very Happy

A good idea, might need to wait until next weekend though once my bike has been checked over
Panthro
Panthro
3Bronze
3Bronze

Male Status :
Online
Offline

Number of posts : 26
Humour : love me, love Gervais
Registration date : 2011-03-13


Back to top Go down

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum