#6

[Grumph]

Where you're checking bucket and shim cams, it's a good (if drastic) idea to cut a free end of the cams off level with the outside lobe.
Doesn't matter which end.
This gives you a clear shot at a bucket.

[speedpro]

I'm familiar with the technique. In this case the "free" end is the exposed end on the other side of the camchain and isn't there any more. On my old CB360 I had a cam cover that was half missing alowing access to the valve gear and the cam sprocket.

[speedpro]

I pulled the water pump off and plumbed a loop of tubing to it, filled it with water and pressurised it to 10 lbs. There were no leaks from the pump. Now I've pulled the head off. There was nothing really obvious and it did look to have been sealed up pretty good. It did show that I need to put a few more water holes in the copper gasket. I seem to remember dropping the sleeves out for some reason, possibly to machine the wire receiver grooves into them and the other possible path for water is between the sleeve and alloy of the block. It has o-rings around the bottom of the cylinders on each sleeve but as they aren't compressed in any way I don't see how they could form a seal. Only the base gasket holds them in. I might drop the sleeves out and see if I can fit an oring at the top to seal the water in. Loctite might have some sort of wicking in sealant that might be useful as well.

I also thought the head bolts weren't as tight as they could have been. I'll have to check correct values and add a bit when reassembling. It may have just been they required to be retorqued after being run.

I'm gonna get into this as 12 years so far is too long from bench to bike for an engine. Who knows I might even have a look at the other bike as well. It's been about the same time for that as well. Might need a secret off-shore account. Of course having some money to put in it would help.

[husaberg]

Finally got round to measuring the cams. Everything checked at least twice.

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 139deg ATDC and closes at 2deg BTDC
Intake is centred at 105.5deg ATDC, measured at 1mm lift it opens at 13deg BTDC and closes at 48deg ABDC.

The numbers seemed odd and not what I remembered. Anyway I had a look around inside and found the original readout sheet from Franklin Cam Services. It was dated 11:44AM Thu Jul 6 2000 to give you an idea how long this engine has taken to get into a bike. The suggestions were:

Exhaust centred at 110deg BTDC
Intake centred at 105deg ATDC.

Little bit out but obviously the intention was there. I'll adjust it tomorrow and measure the timing with the cams installed where they should be, if I can be bothered. Lift is 5.2mm ish. It's near impossible to get the DTI onto the buckets and I had to use a match screwed into my DTI to get down past the cam caps and the lobes.

the exhaust timing should that be

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 39deg BBDC1̶3̶9̶d̶e̶g̶ ̶A̶T̶D̶C̶ and closes at 2degB̶T̶D̶C̶ ATDC?

[speedpro]

the exhaust timing should that be

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 39deg BBDC1̶3̶9̶d̶e̶g̶ ̶A̶T̶D̶C̶ and closes at 2degB̶T̶D̶C̶ ATDC?

Nope. Measured at 1mm lift.

At .1mm it opens at 115deg ATDC and closes at 23deg ATDC.

This is considerably retarded from stock though exactly how much I haven't measured. The setup was for a forced induction engine which has always been the intention. The other side is that the intake cam is advanced.

[Pickle]

. Might need a secret off-shore account. Of course having some money to put in it would help.

Think I can help you there - just send money

[speedpro]

Got a radiator plumbed in and held on with bits of string, just to get it going. So much to do after I get it running.

And then today a box turns up on the doorstep before I went to work. More watercooled bits with the start of hopefully some very trick porting. It's going to be very hard to concentrate on just one thing.

[F5 Dave]

So are you going to run U tube between the head & barrel, or separate rads?

[koba]

Got a radiator plumbed in and held on with bits of string, just to get it going. So much to do after I get it running.

And then today a box turns up on the doorstep before I went to work. More watercooled bits with the start of hopefully some very trick porting. It's going to be very hard to concentrate on just one thing.

Have you run inlet auxillary inlet ports like that before?

I thought I may have pused mine out too far in my latest grinding frenzy but they aren't that far out.

[speedpro]

As long as the piston has support at the rear it shouldn't be a problem. I have always had similar porting on MB100s.

[speedpro]

Went to JC's this arvo and had a play on the dyno. It most surely did not want to go. In the end we had it sorted a bit and could start it with no drama. I'm running the standard CV carbs and they need a finger down each just to the slide which makes them respond to throttle. It was so bad I took the cam cover off to double check the cam timing. It looks good, the timing marks are pretty close to perfect, but I've decided to measure it properly anyway. We pulled the revs up quite high without load and it sounds sweeeeet and revs pretty freely. I'm going to have a look at the sense hole in the bottom of the slides and may try drilling them out a bit. I had a pair of CV carbs on another bike with no airbox and they were awesome carbs and only made 2hp less right at peak compared to mega$ smoothbores according to the guy I bought it off. Giving it throttle at low speed resulted in standoff out the carbs about 20cm. We checked blowdown just to see and it was all good. It looks like it'll be good so will perservere with it.

[crazy man]

so did you have a airbox on it or not? would say you would have to go to about 135-140 main jets without the airbox

[speedpro]

no airbox. The problem is way down the rev range just as you open the throttle. Haven't got to the mains yet. I know from experiance in the bike shop that these carbs are a problem even on a stock bike. FI or a simple manifold with a single newer carb would simplify things. I need to try tuning it before I ditch the stock carbs though.

[Sketchy_Racer]

no airbox. The problem is way down the rev range just as you open the throttle. Haven't got to the mains yet. I know from experiance in the bike shop that these carbs are a problem even on a stock bike. FI or a simple manifold with a single newer carb would simplify things. I need to try tuning it before I ditch the stock carbs though.

If they are CV carbs they need trumpets or airbox on them. They wont open the throttle slides at low RPM with the correctly directed air flow.

[crazy man]

both my nc30 and zxr with cv carbs with no air box dont rev out under load but seem fine with no load