Yamaha szr ,will not start ,HELP

Nitram

Member
UKGSer Subscriber
Joined
Nov 21, 2018
Messages
22
Reaction score
7
Location
Stafford
My yamaha szr 660 will not start ,the only way to start it is to remove tank ,air box and cover the end off the carbs with the tea towel,photo three.starts right away. Been to the dealers they cleaned the carb and adjusted the valves.was ok for a week .not started for a week ,back to square one ,not starting.new plug and the bike as only done 3500 miles ,( probably because it will not start) two owner me the second ,it's mint,that's it folks ,help wanted ,any ideas?
 

Attachments

  • image.jpg
    image.jpg
    95.1 KB · Views: 1,203
  • image.jpeg
    image.jpeg
    233.9 KB · Views: 1,830
  • image.jpeg
    image.jpeg
    222 KB · Views: 1,130
  • image.jpeg
    image.jpeg
    133.5 KB · Views: 1,009
The bike starts when you choke it with the t towel(how did you find that out?!).
Is the actual choke mechanism working?
Ps your in the wrong section, though I suspect it may be for sale soon enough!
Hope you get it sorted.
 
Is the vent in the petrol cap blocked?
When that's happened to me in the past, the Bike would always start / run for a while and then gradually wheeze, misfire and stop.
The clue being a sucking /hissing noise if you open the cap slowly with yer ear to it.
Hope that may help the process of elimination.
Good Luck.
 
Blocked / stuck choke

Blocked pilot or idle jet / enrichment venturi

Split diaphragm


Pop the float bowls off and remove the floats / needle assy

If you can, see if you can find some one with an ultrasoniic cleaner who can drop the carbs into for a while
 
Well the best offers a £1.00,the choke works fine, the towels a old thing from years ago.
 
Check the vacuum hoses, particularly if the fuel tap is operated by it.
Then take a step back, you said it was ok after the carb was cleaned and valve clearances done. Ask the dealer if the clearance was way out.
 
No it runs sweet ,when you get it running don't miss or cut out ,thanks m
 
My Baghira had the same engine, if I left the fuel tap on it would not start next day, but it would be fine while left at work!! I was advised to turn fuel off just before I got home and let it run dry, started doing this (most times) and never had a problem again. If I did forget I would have to drain carb and then it would be ok.
Al.
 
My Baghira had the same engine, if I left the fuel tap on it would not start next day, but it would be fine while left at work!! I was advised to turn fuel off just before I got home and let it run dry, started doing this (most times) and never had a problem again. If I did forget I would have to drain carb and then it would be ok.
Al.
I have a Baghira and follow the same procedure. Turn the fuel off, leave the engine running until it cuts out and then it'll start the next day. As long as you turn the fuel back on :D
 
Yes ,thanks for that,but to turn the fuel off ,the take has to be removed,but I will try it.got it running yesterday and just been out to it ,will not start unless I cover the carbs .
 
Ah. Sorry. The Baghira has the old style fuel tap.

Found this on an MZ forum with the same issue:

"Also prone to float needle sticking, a little tap on the side of the float chamber usually cures that. Whenever I start mine after periods of laying up I always drain the float chamber via the drain screw, which has the benefit of dropping the float and getting rid of any water and unwanted stuff in there."

The bloke finally solved the issue by installing a new spark plug despite believing the original was OK!
 
Another guy fixed a similar problem by turning his pilot screw out seven turns - i.e. more than standard.
 
Another guy fixed a similar problem by turning his pilot screw out seven turns - i.e. more than standard.

Most idle mix screws would have fallen out after around 4 turns :D
 


Back
Top Bottom