gs1000,cam is out

[greg becker]

hi yall.My Saga continues!You may recall that i want to change my cam chain.I need some feedback on another aspect of this.When,in the course of tuning,I checked the timing and found that when ALL other things are as they should be the inlet cams' notch is not pointing to 90degree's but more like 85.She runs!In fact SHE pull like a train.But its not hard to induce a backfire,under power.And she farts and burbles,quite attractively,when i back off from power.IS THERE ANY REASON NOT TO move the inlet cam ONE tooth forward on the chain,to 19 teeth,if this DOES align the notches????Oh yeah,i Still dont know which year this motor is.And no i have not done the chain.Ill wait untill The Superbikes are done here next week and then crack her open for a rebuild.Ta

[BassCliff]

Hi,

I'm no expert, but I noticed a lot of views but no replies yet. So I had a thought...

I thought the cam timing relied on the number of links between the timing teeth on the cam gears, not the position of the cam lobes themselves. The backfiring could be due to a lean fuel/air mixture.

OK, I'll shut up now and be on my way. Hopefully somebody who knows what they're talking about will show up.


Thank you for your indulgence,

BassCliff

[paco13]

are they stock cams?
Do they have adjustable sprockets?

[greg becker]

Thanks Basscliff.My thinking is that the chain is stretched and that while the number of links is spec the distance is not.And thanks Paco,I cant be sure that they are stock.I will check for a part number etc.No they dont have slotted sprockets.My plugs are a good colour.She starts with the first hint of starter button.When i change the static timing there is no change to the backfire.Ta

[trippivot]

advancing the intake cam 1 tooth is an old performance trick. so moving it from 20 to 19 is just fine.

[hampshirehog]

advancing the intake cam 1 tooth is an old performance trick. so moving it from 20 to 19 is just fine.

Standard set up on a GS1000ST.

[Suzuki mad]

Timing a GS1000 engine is simple with the standard parts. As long as the NO1 arrow is facing forwards and horizontal with the NO2 arrow up (exhaust cam.) Then its 20 pins from the NO2 mark to the arrow a NO3 mark.

Sometimes these can vary a little and not seem lined up correctly. The service length of the cam chain according to the manual is 157.80 or 6.213 (mm/Inches)

If the engine's been modified or has adjustable cam sprockets I can't help.

[greg becker]

Thats what i needed Suzuki Mad..This is good!And Trippivot,I had reasoned out that this was so but really wanted someone to confirm it for me.You'll see that Hampshire Hog states that this is standard on a 1000ST.Im staight off to bsscliff' site to suss it out.Thanks ALL.

[greg becker]

Ya gotta luv it!!So yes,the manual @ basscliff confirms,the length SHOULD BE 157+.But my 20 pin length IS 247+mm.Ive checked double checked.147!!!The chain sits on the procketts correctly.Its its its what is this??????OH yeah,the 21 pin length IS 157+.Im going to go now and move the inlet cam one tooth forward,onto the 19th,[and about137+mm]and get her warm[so to speak].Oh yeah,when i say that the notch is not pointing to 90 i should also say that the number #3 on the sprockett is not vertical.moving it to 19 teeth may align it all but 'what the' is going on with the length?

[Steve]

Are you counting the pins correctly?

When you measure the length, the pin that is at the beginning of your measuring tool is not ZERO, its #1.



.

[greg becker]

Hmmm,Thanks Steve,ive just come from moving my inlet sprockett[and now the notch is horizontal]But she runs bad and was hard to start.Very slow responce to the throtle.I see in your diagram that youve got 21 pins,Ive set mine with 20!At least i started that way.And in fact im going back to the cave now to return it to 20[at least she ran well][but not perfect][I LIKE PERFECT]Ta