What's wrong with my GSXR?

[Lawsome]

I have a Y 750 that I bought at the start of the season and the battery was a bit temperamental, so bought a new one. Been fine spring/summer/autumn once a week on average (fires up right away) but went out on an all-day run a few weeks ago then came back to it a week later and it wouldn't start.

I can start it every time with a bump and ride it around a fair bit, so not sure that the Stator/Rectifier would be the issue given the battery doesn't seem to gradually die? But as soon as you stop it won't start again.

Unsure if relevant to the problem but I've noticed more and more when you try to open it up - the bike chuggs/splutters/hops as if fuel supply is getting chopped off.

Edited by Lawsome on Monday 18th November 01:26

[anonymous-user]

Stick a multimeter across the battery and rev it to 5K. It should be 13.5-14.5V. That’ll rule out the charging. I’d be inclined to swap a new battery in regardless before you begin.

HTH

[Wildfire]

Have you checked the battery connections and connections to the coil / coil packs?

[mygoldfishbowl]

Wildfire said:

Have you checked the battery connections and connections to the coil / coil packs?

... and starter relay.

[jjones]

yonex said:

Stick a multimeter across the battery and rev it to 5K. It should be 13.5-14.5V. That’ll rule out the charging. I’d be inclined to swap a new battery in regardless before you begin.

HTH

This

[Lawsome]

Thanks for all the feedback guys, very helpful. My mechanical knowledge in terms of fault finding is pretty poor, I wouldn't know where to start and the GSXR pages I posted in weren't actually that helpful.

Changing/checking everything mentioned can't be a bad idea anyway on an old, high mileage sportsbike - I'll get everything required and get on with it.

Thanks again!

[smack]

As someone with a Mega Mileage GSX-R of that vintage, if it is going to go wrong I have been through it.

Rectifiers are not usually an issue with them, and the workshop manual has a good flow chart for working out what is wrong. I would look it up if I wasn't overseas. But start with your voltages at the terminals, when running are you seeing 14v ish? Rectifiers with these either work or don't so I'd probably head straight at looking at the output from the stater. It is a simple test, pull the connector from the stater and do a few tests with a multimeter. You will have 3 phases of AC current, and check you are getting the right Volts AC out of each phase. If you are not getting enough charging volts, I would bet a winding is damaged and the charging circuit is down on power. Have a search for a Suzuki Workshop manual and it will tell you how to test it. I had a winding die, can't remember what mileage, around 50k as a guess.

Good luck.

[smack]

Lawsome said:

Changing/checking everything mentioned can't be a bad idea anyway on an old, high mileage sportsbike - I'll get everything required and get on with it.

How high is the mileage?

[ylovebuffalo]

I stick new plugs in for a starter...helped me in the past..with the spluttering etc.. sounds like they may be degrading?