Desperate for help GS450 wet fuel height

[pete]

How certain are you that the diaphragms are good?

Reading your latest post reminds me strongly of my experiences with the stock 450 carbs when I was trying to get them right and kept adjusting jetting and fiddling and was having issues with surging at low throttle positions, and generally just not running right. I also had some symptoms like you describe although it was more like the carb was spitting rather than clicking, but we're talking a number of years ago here.

In the end, I discovered both diaphragms had minute tears in some creases that I figured out had been there for a while and I'd just not looked close enough to see them.

Tears in the diaphragms will interfere with the ability of the vacuum to life the slides, so they're going to give you inconsistencies, and my limited experience tells me you'll notice them more at idle and low throttle positions.

My solution was putting some GS500 carbs on as they're a bolt on replacement and are lighter, and most definitely were cheaper than replacing the slides and diaphragms. You won't be able to run the stock airbox though and will need to figure something out there. My choice was velocity stacks with a foam filter over the top.

[rekidiw]

Hey Pete,

Glad to hear back from you.

I've checked them both with a flashlight. Actually just check the right side again 2 days ago but maybe I missed something. I will have to take another look.

While I have you here. What do you know about the position of the signal generator plate?

Today, stumped and desperate, I started to check random things and came across the signal generator plate. I loosened it while idling and twisted it counter clockwise just the little bit that it could go(about 3-4 mm) and it started idling higher and stronger. It didnt have that loping sound of an unhealthy idle. I searched around to find exact information on where it should be positioned and didnt find anything. I have a manual but hoping to get a 2nd opinion since the manuals have proved to be wrong more than once.

[pete]

With any luck your diaphragms are good, but thought it definitely worth a mention given the similarity of the symptoms.

Hmmmm good question! Been a while since I've had to align that for timing and pretty much all my mechanical work recently has been on the Kat.

If you rotate the plate clockwise, I believe you're retarding the ignition, rotating counter clockwise will advance the ignition. Be aware at idle if you advance it too much that when the RPM's get up and the advance counter weights kick in, the ignition may be too advanced. I don't think that's possible with the stock adjustment range though.

From memory the only adjustment you need to do with the signal generator plate is very minor and needs to be done in conjunction with a timing light to get it in the right position. The manual will tell you how to do that, I can't remember the marks to align with off the top of my head.

Which manual do you have? I'll endeavour to have a look in my factory reprint to see what it says on the matter.

[Gorminrider]

The timing plate of the electronic ignition is "set" in place. There's very little adjustment because it's not meant to be adjusted. You are barking up the wrong tree unless you discover a flaw in the wires- (check these for chafe) or even sensor coils (check these for looseness-I discovered one once that I had to glue!)