How to set manual chain tensioner, GS1100 top end pitfalls?

[Guest]

Hi everyone, been away from the board for a few months doing other stuff buy still getting some riding it now that I'm back in NY. A few quite questions here about a GS1100 engine I'm putting back together for a friend. He bought it last summer, rode from Philly to Asheville, NC to meet me on my way up from ATL and lets just say the trip ended with me pressure washing the oil off him in a Scranton, PA car wash at 3am due to head gasket and VC leaks which we were not able to fix on the road. Retorquing helped for a few hundred miles but then it was oiling the tire and everything behind him again... Bike sat for a few months in Ithaca until we could get it to my place.

Anyway here are the questions:

Head gasket - We have an Athena gasket set with MLS gasket, the kind with a black coating on both sides. I know MLS have a bad rep in some circles but everything looks good with the surfaces so I've got some hope. Is there a source for the old style gaskets if this doesn't work? Also, stock torque? 29ft/lbs is the way to go?

Chain Tensioner - The bike has an APE tensioner that some PO in the past over tightened, eating up the rear chain guide. I have a new one in hand but I'm not sure how to tighten the tensioner correctly.

Studs - Any chance the studs have stretched? With that low a torque spec I wouldn't think so but I really don't want him to have issues with this engine next summer! Two of the studs came out with the bolts (front, center). Is locktite Red good for those or should I get actual bearing and stud locktite?

I'm replacing the base gasket and head gasket, are there supposed to be any orings in there? I seem to remember reading something about them but I don't see any pockets in the head.

Thanks for your input, I'll be checking back tomorrow before I dig in to reassembly. I'm out of town right now.

/\/\ac

[tkent02]

Chain Tensioner - The bike has an APE tensioner that some PO in the past over tightened, eating up the rear chain guide. I have a new one in hand but I'm not sure how to tighten the tensioner correctly.

Use a stethoscope, run the engine at idle, tighten the chain until the jingling noise goes away, if you go tighter you will hear a scraping noise as the chain is sliding tightly against the guides. There should be a silent place in between the two noises, that's where you want it. If you can't get it perfect, err on the jingling side.

This from instructions for manual tensioner on a Kawasaki Concours, but it should work on a Suzuki unless someone smarter posts something better. On the Concours there was a very tiny silent spot between the two noises.

[nhgsguy]

The APE instructions are - To set the tensioner adjustment,rotate engine forward while screwing the tensioner in.When you feel the engine tensioners parts (guide,rollers,ect) make contact with the moving cam chain,back tensioner bolt up 1/4 turn and tighten the jam nut.

[Macmatic]

Man... I was all set to go with Tkent's method but now I don't know. I've got to assume that APE know's what they are talking about but the other method sounds like it might be more precise, if you get it right.

I came home to an unexpected dead car in the garage so as soon as I get that out of the way I'll be diving into the bike. I'm hoping my buddy and I can get in a few more riding days this Fall. He hasn't had (2) wheels since July!

/\/\ac

[trippivot]

I go a little tighter than 29 I use 32 or 34 on the head with stock studs. 100 inch pounds on the 6X1 cover bolts.

the tensioner I get it so there is 3 - 5 crank degrees of play not tight not loose just a little wiggle when you have a wrench on the crank turning it over. I do it when you can see the camchain sprockets in relation to the crank movement. it is not that sensitive- well it is a sensitive detail but not as important as drive chain alignment or cam timing alignment. you just do not want it tight as a banjo string and you do not want the camchain slapping when it it idling. clear as mud?

[posplayr]

The APE instructions are - To set the tensioner adjustment,rotate engine forward while screwing the tensioner in.When you feel the engine tensioners parts (guide,rollers,ect) make contact with the moving cam chain,back tensioner bolt up 1/4 turn and tighten the jam nut.

are these instructions documented anywhere on the web? That is not what APE told me over the phone.

IIRC, they said there needed to be alot of slack in the chain(1/2"). Of course the question was in relation to the HD rear cable guide breaking so what else would they be expected to say.

[Macmatic]

I think I'm going to re-read these comments tomorrow and then just "use the force" to get it where it feels right unless someone else chimes in. I feel confident that I can get it somewhere between too tight and too loose.

Any thoughts on stud lock?

/\/\ac

[posplayr]

I think I'm going to re-read these comments tomorrow and then just "use the force" to get it where it feels right unless someone else chimes in. I feel confident that I can get it somewhere between too tight and too loose.

Any thoughts on stud lock?

/\/\ac

U might be interested in this thread. I have come to the conclusion after having had this happen that the chain needs to be tight but that some small deflection is best so that the tensioner is not overly flexed. As a general rule, when under acceleration, the timing between the crank and the cams is defined by the chain length alone and not any slack because that part of the chain is under tension. When you let off the chain goes slack and will change the relative timing. So cam chain tension primarily affects the cam timing when under deceleration only. That can probably be 2-4 degrees and you will not notice the difference.

So I have chosen to tighten the chain until there is some slack at mid point in the cam chain (say +/-0.125"). This is still small deflection occurs with perhaps 5 lbs at the middle of the chain. I did not calibrate it but, it is just to give you an idea.

The only trick to measuring slack is that you have to reverse the chain a bit till you get to the middle of the slack. So in other words, when you crank the engine over the chain goes into tension because the crank is pulling the chain down and tensioning the chain between the cam gears. If you let up and start to reverse, the chain will get to a maximum slack before it starts pulling from behind. You want to measure the slack at that maximum slack condition.

Now Terry (HeadsBikesMopars) described another more elegant way using a stock tensioner. He measured would install a automatic OEM tensioner; lock down the rod and remove the tensioner. He would then measure the distance that the plunger was pushing out from the housing (the part that pushes on the rear tensioner). He sets the manual tensioner for the identical depth and installs it.

It would be interesting to note what the slack is at this tension and then that could simply be replicated. Otherwise he claims to have had excellent results from this approach.

http://www.thegsresources.com/_forum/showthread.php?t=139202

[almarconi]

are these instructions documented anywhere on the web? That is not what APE told me over the phone.

The instructions that have been referenced are printed on the back of the cam tensioner package.

[posplayr]

The instructions that have been referenced are printed on the back of the cam tensioner package.

Interesting I dont remember ever seeing any; I only bought one new and that has been a while now. And APE did not mention them either just how much slack there was.

I assume you adjust your tensioner when you adjust valves; any idea how much slack there is on the chain at midpoint between the cams using this proceedure? It sounds like it would be fairly loose but it depends on how you decide there is contact of course.

If you back off from first contact does that say the tensioner is set to be at a point of no contact and it is there to restrain chain movement as it pulls and moves with RPM . That doesn't even sound like a tensioner; more like just setting a guide distance.

I'm sure that the way Rapid ray set mine and the way it is set even now we are well beyond just 1/4 turn from first contact. There is likely tension due to flexure of the rear guide. As show in the thread you can go too far and break the guide.

I think racers probably wanna control the cam timing better and put the tensioner on tigher than APE's reco. I have about 3500 miles on my motor and dont seeem to have issues with my adjustment or tensioner damage.

Thanks for the info.

Jim