Need a solid 9 hp motor recipe...

[loudaddy]

Ok i have a 6.5 clone motor, and a comet TAV-30 the hp rating is 9 hp on the TAV, so i guess i shouldnt exceed that so the torque converter lasts.
Looking around i found that i could get close by removing governer and rejetting carb and adding a header. I realky dont know how well the stock cam will do. I would like to know if i should add 1.2 or 1.3 rockers to stock cam or switch the cam to a .265 cam.also what rpms would i be at ith each cam? What is the point at which the billet rod and flywheel are needed? Any mods that can be don to torque converters to squeeze more hp?
I guess if anyone has any good combos in that hp range i would appreciate input! Tbanks !
Lou

 

[supernova]

There are those who would disagree but removing the governor without getting a billet flywheel is foolish, a billet rod as well IMO. The 6.5 stock actually makes 7.2hp and by adding a cheater spring you can exceed the 3600RPMs by quite a bit. See "why remove the governor" in the clones sub-forum. I spin 5000 revs and have to be making some good HP given the fact my DB will go 40+ all day long. Should you decide you want more then get the flywheel and go from there. :thumbsup:

Removing the governor without adding a billet flywheel is foolish, plain and simple!:hammer:

 

[loudaddy]

Thanks, i really didnt plan on not getting billet parts, was more concerned about rpms and hp ability on tav-30 units even though they are rated at 9 hp.
What diiferences in rpms and power eould there be one cam vs the other?

 

[mmisterbungl]

Better watch out!

 

[loudaddy]

I AM GETTING BILLET PARTS!
Now, that that IS established, how about those mods / combos?
Lou

 

[Oldschool]

See supernova's reply.

Add 14cc head from a GX 160 clone ( 5.5 hp )
Aftermarket air cleaner and velocity stack.
Header.
4 deg offset timing key
And reject the carb as required ( 91 jet is probably all you need )
See the cheater spring mod to keep you governer but allow you to rev to 5000. At that speed your stock engine will make the power you want. Increase spring tnsion on your TAV secodary to keep it from shifting up too soon and you will make better use of the modifications sugested.

Search these sugestions lots of good info posted ( and I have typed this combination a lot lately, it works )

 

[vette66_00]

9hp is super easy. Cam (the cheap $50 one), Flywheel and Rod, rejet, intake, at least 4 deg advanced, and exhaust pretty much as Oldschool said.. Infact with the cam you will have a higher amount of power.

The below Dyno is minus the cam... Considered a box stock engine with a 1/2" exhaust and muffler.

 

[Strigoi]

Add 14cc head from a GX 160 clone ( 5.5 hp )

not all of them are 14cc heads. only the old ones are, the newer ones will be 18cc.

 

[loudaddy]

9hp is super easy. Cam (the cheap $50 one), Flywheel and Rod, rejet, intake, at least 4 deg advanced, and exhaust pretty much as Oldschool said.. Infact with the cam you will have a higher amount of power.

The below Dyno is minus the cam... Considered a box stock engine with a 1/2" exhaust and muffler.

is that dyno chart with the governer on or cheater springs ?
my head measured 19cc by my buddy who owns a machine/speed shop.
i cleaned up the ports and cut back the short side radius on the exhaust side.
what drivability differences will there be with the stock cam and 1.2 rockers vs the 265 cam and stock rockers?

 

[jprice]

this should give you some ideas
NR RACING

 

[vette66_00]

is that dyno chart with the governer on or cheater springs ?
my head measured 19cc by my buddy who owns a machine/speed shop.
i cleaned up the ports and cut back the short side radius on the exhaust side.
what drivability differences will there be with the stock cam and 1.2 rockers vs the 265 cam and stock rockers?

This would be Gov out and on stock springs. You can see that it starts to die off around 4800 where the stock springs and cam start to be inefficient and start to cause floating. Around 5400 you really hear the valve float.

As far as the cam vs rockers. Go rockers if you plan on keep the gov in and go cam if you take it off. Of course after you have the proper parts installed. :wink:

 

[olajoe808]

Lou to be honest with you. On a stock motor, just about anything you do to it will increase it's performance. Whether it be modifications to the head, carb, cam, or header the motor will instantly wake up. I wouldn't get to fixed on a specific output, or combo and the reason is the level of output with a given set of parts will vary from one motor to the next. Good luck!

I AM GETTING BILLET PARTS!
Now, that that IS established, how about those mods / combos?
Lou

 

[Oldschool]

9hp is super easy. Cam (the cheap $50 one), Flywheel and Rod, rejet, intake, at least 4 deg advanced, and exhaust pretty much as Oldschool said.. Infact with the cam you will have a higher amount of power.

The below Dyno is minus the cam... Considered a box stock engine with a 1/2" exhaust and muffler.

If he adds the 265 cam, he will need springs or it will float sooner and not gain as much. Float the valves on a clone and you weaken them progressively as well as risk snapping a valve.

Add more spring and you can rev it higher possibly into a zone where things get risky for stock rotating parts.

Just go with what I sugested louddady.
Its an easy starting point that doesn't involve a lot of money or time. You don't even have to pull the engine from the frame to do it.
Later you can add more stuff but remember a 30 series Torque is not rated for more than 9hp ( it can do more but eats belts ) and higher RPM will try and fling the belt from the clutch meaning more slip and again more wear.
You can your 9 hp at around 4800 rpm ( I did that and a bit more ) and still have a good reliable motor.

 

[loudaddy]

See supernova's reply.

Add 14cc head from a GX 160 clone ( 5.5 hp )
Aftermarket air cleaner and velocity stack.
Header.
4 deg offset timing key
And reject the carb as required ( 91 jet is probably all you need )
See the cheater spring mod to keep you governer but allow you to rev to 5000. At that speed your stock engine will make the power you want. Increase spring tnsion on your TAV secodary to keep it from shifting up too soon and you will make better use of the modifications sugested.

Search these sugestions lots of good info posted ( and I have typed this combination a lot lately, it works )

i ordered a 90 jet and a 140 e-tube,do i need a manifold? i have been looking at the brute mini bike header with muffler.i dont know if it will work on my bike yet.thanks
my head is a 19 cc oldschool, i can have it milled, what do you suggest on c/r?

 

[Oldschool]

If your not going to make any other changes leave it as it. ( head )

Later on I sugest you buy another clone and add some beefed up parts to that and a flat top piston. Move your 18 cc head onto that for 10:1 a good compression ration. If you mill ( to run raised compression with a dish )to get it higher then later a flat top will push you into 93 or 94 octane requirements.

If you have to mill it I don't think any more than .040 would be good. That brings you around 10 to one for now and a little over 11 to one witha flat top ( depending on tollerence stack up in the engine it might be a little less ).

Clones are cheap and everywhere so are clone and Honda parts. You can start collecting now for a second motor. A used Honda with .002 wear (from say a broken presure washer ) with a flat top and fresh set of rings would be good next or another clone no matter....
Seasoned engines like that are a bit looser and faster anyways....

You need an airfilter and velocity stack with a header.
You should do a mild port job ( I think you said you did ).
Timing jetting.....
Your mostly where you want to be on a 1st engine.

 

[loudaddy]

ok, i will do the cheater spring,air filter, jetting, & header
the brute headers look like a good deal.
thanks for all your help guys!

 

[Oldschool]

ok, i will do the cheater spring,air filter, jetting, & header
the brute headers look like a good deal.
thanks for all your help guys!

One step at a time.

Left foot right foot, left foot right foot,left foot right foot, left foot right foot.

 

[loudaddy]

Eye eye cap'n
:thumbsup:

 

[steveweippert69]

so what is the true ability of the tav as asked? can it be worked to hold more power of is it just weak?

 

[Oldschool]

so what is the true ability of the tav as asked? can it be worked to hold more power of is it just weak?

It will take as much power as you throw at it, then it will twist and break.
Progressively more power beyond 8 hp will begin to slip and wear belts at faser and faster rate. And depending on how hard you are on the throttle.
A reasonable person might get more belt left and fewer worn bushings with a likght throttle than a person who drives the piss out of it with less real power on tap.

No easy answere.....