Dr. Jekyll and Mr. Hyde ( a pair of KZ400s)

Nebr_Rex

Member
doc_rot said:
will removing that much material cause the cam chain to have extra slack? will the tensioner be able to take up that much?
Just had another wild idea.
If this does not work I might try machining a pair of custom rods that are longer than original.


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teazer

Well-Known Member
DTT BOTM WINNER
I suspect that he means going back to stock height barrels and making longer rods to allow for the lower deck height on the Honda pistons.

The cam chain will probably have enough adjustment in it but it will change cam timing and that will probably need to be adjusted. Another issue is that the liners were not machined to match the block and may be too long and too large to fit in the crankcases.

And have you worked out the compression ratio? With that flat top piston it might be a touch low.
 

Nebr_Rex

Member
teazer said:
I suspect that he means going back to stock height barrels and making longer rods to allow for the lower deck height on the Honda pistons.

The cam chain will probably have enough adjustment in it but it will change cam timing and that will probably need to be adjusted. Another issue is that the liners were not machined to match the block and may be too long and too large to fit in the crankcases.

And have you worked out the compression ratio? With that flat top piston it might be a touch low.
Bingo!
Compression with a stock head [ not milled ], will be around 7.1/1 .
With a head milled .070 and no base gasket, just some 1194 for a sealant.
The compression ratio jumps up to around 8.5/1 . Which is what I'm
shooting for. As for the barrels I am thinking about an aluminum spacer
to take up the difference.


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Nebr_Rex

Member
DohcBikes said:
Buy a klx450 motor and be done with this epic
No room for growth, they are pretty much maxed out from the factory.
Also I'm no fan of titanium valves and replacing them with stainless steel
and a valve spring change. Besides anyone can buy horsepower. It's more
fun making it. There is a saying that goes " if it hurts don't do it ". And
something about repeating an action and expecting a different result
questions one sanity. You might want to avoid this thread.


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Nebr_Rex

Member
For those of you with a KZ440 having trouble jetting the stock carbs for pods. I may have a solution
for the problem. I just finished a little testing using a Dyno Jet kit for a KZ750/4. The differences
between the two are the main body casting and throttle butterfly. The 750 used a 34mm and the
440 used a 36mm. everything else interchanges. The slides on the 440 has 4 holes, 750 has 2.
Engine has the 750 pistons, reground cam, no filters and a freer flowing 2-2 exhaust. I used the
kits largest jets and lowered the jet needle one e-clip position from the directions. Stock 4 hole
slides with the holes drilled out were used first. Currently have 750 2 hole slides that have not been
drilled. It's just a little lean off idle with lowering the needle back down should be cleared up. I'll
be switching back to the stock cam and start reinstalling the fuel injection. While installing the
electronics the carbs will still be used and further tuning will be done.


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Nebr_Rex

Member
I got the jetting real close. The idle mixture screws are 5.5 turns out. That is to far.
Two new jets are coming from jet r us. I raised the jet needle one slot from what
DynoJet calls for the 750. This is with bare carbs, no filter of any kind. Fuel injection
electronics should be sorted enough to get it running. Next up will be checking out
all the plumbing for leaks. Below is a pic of the difference in jet needles.

From left to right... Dyno Jet w/shims, stock Keihin, stock Mikuni BS34. and a pair
for vm Mikunis.


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Nebr_Rex

Member
Started to reinstall the fuel injection plumbing.
As for the final settings on the stock 36cv Keihin carbs.
Largest jet in the DynoJet kit.
Jet needle raised one slot from kit instructions.
Stock 4 hole slides drilled with bit from kit.
38 Jets R Us pilots. (35 stock)
Idle mixture screws 1 1/2 turns out. (5 1/2 w/35s, now
has much better idle and off idle response)
This is with no filters what so ever leaving plenty of
room for tuning with a good set.


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Attachments

Nebr_Rex

Member
Nebr_Rex said:
Started to reinstall the fuel injection plumbing.
As for the final settings on the stock 36cv Keihin carbs.
Largest jet in the DynoJet kit.
Jet needle raised one slot from kit instructions.
Stock 4 hole slides drilled with bit from kit.
38 Jets R Us pilots. (35 stock)
Idle mixture screws 1 1/2 turns out. (5 1/2 w/35s, now
has much better idle and off idle response)
This is with no filters what so ever leaving plenty of
room for tuning with a good set.


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Switched to 40 pilots. My needle and seat were shot letting more fuel in.
Reinstalled the cam I reground. With the stock cam and cam timing
cranking compression was 175 on a fresh engine. With my cam it is
up to 180. I'm going to keep the carbs on this bike. The injectors do
not like being fired at 7500+ rpm on every revolution. I will have to
cut that in half by pulling my signal just off the cam. This means
another rocker box and cam to modify. Starting to work on my GPz
and two pickups and then life it's self have slow progress but I'm still
plugging away.


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Nebr_Rex

Member
I'm still around, just got a little side tracked lately.
Here's some pics I found of Mr. Hyde from a while back.
I'm going to take a little different approach from what
was done previously.
 

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