Resend my activation email : Register : Log in 
BCF: Bike Chat Forums


SR125 starts then cuts out when I try to open throttle

Reply to topic
Bike Chat Forums Index -> The Workshop
View previous topic : View next topic  
Author Message

eastendborn
L Plate Warrior



Joined: 21 Jun 2022
Karma :

PostPosted: 21:31 - 21 Jun 2022    Post subject: SR125 starts then cuts out when I try to open throttle Reply with quote

SR 125 cuts out when I start it. It starts -then as soon as I go to give it revs- it dies.
I spoke to a motorbike mechanic today and he asked me what I put in the tank. I told him some Redex (as I had read was ok)
He said it is the Redex causing the problem -but my motorcar mechanic says it wouldn't be that. Any thoughts please?
 Back to top
View user's profile Send private message You must be logged in to rate posts

Ariel Badger
Super Spammer



Joined: 02 Dec 2006
Karma :

PostPosted: 22:51 - 21 Jun 2022    Post subject: Reply with quote

Why did you put that snake oil in your tank? What ratio did you mix it at?
____________________
Bikers make great organ donors, get 115 on your licence today.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

jaffa90
World Chat Champion



Joined: 06 Apr 2016
Karma :

PostPosted: 23:11 - 21 Jun 2022    Post subject: Reply with quote

Sounds like the choke jet is clear but the others not.
Suggest a carb service and fitting an inline fuel filter if possible.
 Back to top
View user's profile Send private message You must be logged in to rate posts

eastendborn
L Plate Warrior



Joined: 21 Jun 2022
Karma :

PostPosted: 00:07 - 22 Jun 2022    Post subject: Reply with quote

I put it in as it misfired a couple of times, and I read somewhere that a guy with a motorcycle said he kept his clean with Redex so I thought it was ok. I put about 40-1 ratio in. I start it without throttle and choke on - then as soon as I try to pull away with a little throttle it cuts out. Some guy said he he thought that was because the air was getting through but no fuel to mix it with.
 Back to top
View user's profile Send private message You must be logged in to rate posts

jaffa90
World Chat Champion



Joined: 06 Apr 2016
Karma :

PostPosted: 00:10 - 22 Jun 2022    Post subject: Reply with quote

eastendborn wrote:
I put it in as it misfired a couple of times, and I read somewhere that a guy with a motorcycle said he kept his clean with Redex so I thought it was ok. I put about 40-1 ratio in. I start it without throttle and choke on - then as soon as I try to pull away with a little throttle it cuts out. Some guy said he he thought that was because the air was getting through but no fuel to mix it with.


As my last post then.
 Back to top
View user's profile Send private message You must be logged in to rate posts

eastendborn
L Plate Warrior



Joined: 21 Jun 2022
Karma :

PostPosted: 00:39 - 22 Jun 2022    Post subject: Reply with quote

Ok thanks for your help,, I'll enquire about getting it cleaned. Cheers Smile
 Back to top
View user's profile Send private message You must be logged in to rate posts

jeffyjeff
World Chat Champion



Joined: 02 May 2020
Karma :

PostPosted: 12:31 - 22 Jun 2022    Post subject: Reply with quote

I would start by making sure your idle air screw is adjusted properly; 1 1/2 turns out from fully seated according to the yamaha club forum. If that does not help, your symptoms suggest a restricted pilot jet. That would be the smaller of the two jets you see when you remove the float bowl. Remove it and clean it out (but don't ream it or you'll likely affect the jet size). Since you have the carburetor apart, best to check the float height is within specification, since float height affects carburetor performance across a range of operating conditions.
____________________
History shows again and again how nature points out the folly of men - BOC
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

eastendborn
L Plate Warrior



Joined: 21 Jun 2022
Karma :

PostPosted: 21:59 - 22 Jun 2022    Post subject: Reply with quote

I removed the fuel filter today -( the bike was stored in a garge for 10 years before I bought it). As the sponge filter (that goes before the metal one) looked shabby - I put it into warm water. It thereby dissolved into like a black ink. As there was a hole in it when I removed it- I guess some of it could have got into the carb. Not good. Anyway, I'm addressing all advice so thanks again blokes.
 Back to top
View user's profile Send private message You must be logged in to rate posts

MCN
Super Spammer



Joined: 22 Jul 2015
Karma :

PostPosted: 12:03 - 24 Jun 2022    Post subject: Reply with quote

Fit a new spark plug.

Or at least remove the plug and look at the condition of the electrode, the side wire and the ceramic insulator.

The engine needs three basic things to run.

Fuel, oxygen and a big phat spark.

If any one of those three is weak then the engine will stall.

(Too much fuel can also kill an engine. The choke is possible still 'on'.

The start procedure:

Chock on. Not 1/2 on but fully on.
Crack the throttle open a tiny amount. 1/8 of a turn. That lets some air in to burn the fuel.
Turn the engine over on start lever or start button.
When it fires you may need to phannie a little with the throttle for a stubborn pig.

Let the hoowur run on full choke until it stabilizes. It 'should' start to idle at a higher speed.
Try to switch the chock off. Maybe hace to phannie the throttle again.

It should then run smoothly but possbly fartanfuk until it is warm enough.

No real need to let an engine warm up for much more than a minute or two. Ride off and just don't give it handfuls of throttle until it is warm. (Circa 5 minutes)
____________________
Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts
Old Thread Alert!

The last post was made 1 year, 268 days ago. Instead of replying here, would creating a new thread be more useful?
  Display posts from previous:   
This page may contain affiliate links, which means we may earn a small commission if a visitor clicks through and makes a purchase. By clicking on an affiliate link, you accept that third-party cookies will be set.

Post new topic   Reply to topic    Bike Chat Forums Index -> The Workshop All times are GMT + 1 Hour
Page 1 of 1

 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

Read the Terms of Use! - Powered by phpBB © phpBB Group
 

Debug Mode: ON - Server: birks (www) - Page Generation Time: 0.07 Sec - Server Load: 0.24 - MySQL Queries: 17 - Page Size: 61.24 Kb