Kawi2strokes.com Forum

Maybe means nothing but.....after I put the 30s on the S3 and did the engine work, I noticed it would break up very similar to yours at certain tunes. One thing you may notice is when it's running about 2500, you can twist the throttle slowly to full with the engine not exceeding 4k, and you may experience a dead spot where the engine dies off before the main takes over and it recovers. If you can get a richer needle for your carb, might be worth a shot.

_________________
74 H2B with reeds and 34mm carbs
75 S3A Ram Air with reeds and 30mm carbs
73 S2A (wife's bike)
71 Yammi RT1B
83 HD Sportster
03 Yammi R1
06 Kaw 750 Vulcan (wife’s bike)
12 Yammi vstar 250 (wife’s bike)

Hi.

Your cylinders.......are they Ebos??

I will take the Higgspeed measurements later today, I'm kinda slow

Regarding jetting:

It depends greatly. With my 109 rwhp reeded cylinders with Jollymoto and Ebos heads I had to use 300 mains to have the detonation within control.

I have those same cylinders on my H2B touring bike today, running Higgspeed and STOCK ignition. I use 270, and the same amount of detonation as with Jollymoto/300 mains AND retarded ign timing!! (mild detonation, only when fully warm)

The Jollymoto are prone to detonation, and a pain to tune. (4 stroking off pipes, detonation on pipes) But the kick they give when hitting powerband is amazing, same with peak power! They are really "GP" fatties. The Higgspeed are A LOT easier dealing with for everyday use!

With stock cylinders and Higgspeed I used 220 mains.

1 thing: I believe the pretty square exhaust shape of yours tend to make the returning wave "short and strong". Good for peak power, bad for middle range power as this, in combination with steep last cone shape of pipes, gives you a very strong returning wave -messing up things just before pistons closes transfers.

Do you have other pipes? Even stock pipes? I can almost guarantee if you try stock pipes the problem is solved due to the issues mention above. But then again, you got a more linear power curve, without that big hit and great peak power......

Jorgen

_________________
___________________________________________
72 H2, 72 H1B, 74 H2, 74 H2 Cafê Racer, 71 F8 Bison

Ding ding! We have a winner.. Yes they are EBOS Seller told me engine was build't in mid 90's?? (ran like crap when i got it) So i called ebbe right away and he told me porting still is the same in his 128rwhp engines today Infact he had one on his bench that he was restoring so we compered porthight's directly on the phone, and they matched! Told him it had vm34's and he just laughed.. and told me lectron's and good pipes would cure it. Thank's for sharing Jorgen, but what do you use for nozzles (needle jet's) Have to do some garden stuff now but will be back later..
here's a ebos stagell (same porting as mine but tomcat pipe's) dynosheet:
http://www.ebos.se/pics/olle006.gif

Yeah, thought so. I recognized the ex port. And yes, Ebbe is a wizard regarding these old 2-strokes.

I use everything from 159p6 to p2 (p2/4 for my Ufoed pport 94 rwhp caferacer) with either 6dh4 or 6dh3 needles.

P5 in combo with 6dh4 or 3 is a good combo for VM 34 non-Ufoed set ups.

I have 40mm Lectrons in my drawer, and 2 kawi friends of mine has sucessfully ran such on their Ebos-H2's. And another one has a Chris Ritchie reed set up, Jollymoto and Lectrons. And another runs the 40mm, but bored up to 44mm. That engine is today in a drag racer, producing 152 rwhp with drag pipes at 8500 rpm I believe.
So, Ebbe makes the Lectrons work on street bikes. You have his squish heads as well?

Jorgen

_________________
___________________________________________
72 H2, 72 H1B, 74 H2, 74 H2 Cafê Racer, 71 F8 Bison

Ok, My 34's has P2's and dh4 needle wich are to fat at flatspot.. Good thing about the nozzles i
bought for my TM's is that they also fit the 34's Been hunting for used 40mm. lectrons for quite som
time now with no luck.. Btw. do you know if 40-44 lectron share same body or is 44 bigger?

About head's.. Suppose so? They have dual angle squishbands and read 160-165 psi. on my gauge.
But dual squish sound's a little oldschool to me..? So maybe head's could be improved?
About Zeel.. Is it easy to install (they come with no connectors, right?) and tune?

_________________
___________________________________________
72 H2, 72 H1B, 74 H2, 74 H2 Cafê Racer, 71 F8 Bison

Lars: VM34 and your TM does NOT share the same needle jets! VM use 159-series, TM use 389 series. They are interchangeable as far as I know, but still they are different!
Are you running 159-series in your TM38?????

About Lectrons: Only thing I know is the 40mm can be bored out to 44mm. That may mean they are the same regarding body....?


About your compression: 160-165 psi may be too high........

You got detonation?

_________________
___________________________________________
72 H2, 72 H1B, 74 H2, 74 H2 Cafê Racer, 71 F8 Bison

Yep, i run 159's in TM's now, usally TM has a 389 nozzle but mine are sled rackstyle carb's and have 327 nozzle's..(ski-doo special?)
And 159 are identical to 327 only shorter, had to delite the ring between jet and nozzle and add 2 washers to get mj in lowest position possible, no probs so far..

Yes, had it deto but was to lean also then (needles) usally not a problem

Yep mine hit hard to.. Got stock pipes and your prob. right, they would cure flatspot but kill all the fun.. The fbg. are dead (thank god) as i cut them and used the header, hated them anyway..
with fbg. i had flatspot all way from idle up to 7000k!! tryed them with stock topend also to short and skinny! Would try
K2-tec pipes if i could afford them Btw. Anyone have some info about taperd vs. paralell header on our bikes? Mine has a 1,5
degree taper and i know taperd is supposed to make more power but is that a fact on h2?

Here's a pic. of Mikuni brass, from top: #389 #327 #159

Tapered headers will make better power, assuming all angles etc are in order.

_________________
I am just a man working in a tin shed.