Just wanting to benefit from the experience of anybody out there who’s running a modified Savage.

I’m now up and running with my motor, which will be putting a fair bit more power through the machine than original.  It has:

Compression raised to 9.3:1
Ported head
High lift cam (from lancer)
VM carb (from Lancer)
Freeflow pod air filter (from Lancer)
Raask exhaust

Lancer ran a similar motor and saw 45hp at the wheel, but that was without the head porting and compression increase, so this engine could be putting out towards 50hp at the wheel – around double a standard Savage (I need to get it on a dyno some time and will post results, but more of that another day).

Two things I need to ask, to see if anybody out there has experienced these problems.

Despite using upgraded clutch springs, she's giving me clutch slip when I wind her on at top end – has anybody else found that with a tuned Savage?  I guess when you're increasing an engine's output by so much it shouldn't be surprising.  Anyone else encounter clutch slippage, even with uprated springs, on a tuned Savage? Is there a good kit available to further upgrade the clutch?

I also seem to be getting a 'jerking' through the transmission/drive when I start to wind some power on.  Now, it may be the clutch juddering, or I wondered if maybe the extra torque was stretching the drivebelt and causing the teeth to catch – I can only describe it as feeling similar to a chain jumping teeth on a badly worn sprocket, but the belt is new and tight and the hubs are in good condition, so I don’t think the belt can be skipping teeth.
I have no real experience with belts, but I seem to get noise from low behind my left ear when this happens, making me think the drivebelt isn't happy.  I just fitted a new belt, and tensioned it so I can just turn it 90 degrees with fingers and thumb.

And pointers gentlemen?

I am not even close to where you are, but I have a pod filter, 86' stock jet, and MAC slip-on.  I was getting some slippage so I replaced the pressure plates, clutch plates, and springs with stronger EBC pieces.  I am still getting slippage especially at the top end of 3rd and 4th.  I'm trying to get a new baskets to see if mine is wearing.

I had clutch slip on my 350LC after I'd tuned it (good sign elsie was making more power) and one thing I tried was preload washers, make them the same o.d. as the spring or just a few thou less,i.d. just slightly more than the post the bolt goes into and 3-4mm thick.
Ideally you want them thick enough to just be short of coil bound when the lever is against the bar.

Clive W  

That's what I though too, but I only get slippage in 4th gear when I really get on it.  It never slips in 1st or 2nd even under full acceleration.  My feeling is that with the higher gearing of 4th more torque is needed to move it and that is more than the clutch can handle.

Logically the highest engine resistance is seen when air friction absolutely stops the bike from going any faster.  Air resistance at MAX, enough to overcome engine output at peak HP and torque -- slip occurs then if not earlier.

Clutch fails to handle the load at 200% normal loading -- surprise surprise.

Things you can do -- roughen up the steel plates to give them a more positive bite (will result in rapid friction disc wear) and INCREASE the spring pressure (double springs (inner outer), for flat wire springs look up DIE SPRINGS in your browser for design options at heavier loadings.

Hey, you just answered one of my long term questions -- what part/subsystem was next in the failure chain to higher HP in a Savage.

Interested to see what you come up with to fix it.

Thanks!

Oldfeller

I was thinking more along the lines of a finishing sander with 180 grit paper, but thinning the steel disks some with a surface grinder offers the option of stacking in another steel and another friction disk (using the already worn friction plates after deglazing the surface as they are thinner).

Throw through the actuation system can be tuned with a custom rod to accomodate the slightly taller stack up.  As long as it will push enough to loosen the stack, you are good to go.

Adding a steel and a friction does actually increase the system's capacity in a real and practical fashion.

Have seen such tricks played before, using stacked belville washers to provide "spring" force in a clutch pack simply that had no room for the standard spring any more because it was full of plates.  Actual throw to unlock a clutch isn't near as much as them springs would indicate.

Next thing to look at is a taller basket, some mgfs tend to use the same design with taller basket in the bigger models.  Gotta miss the cover though.