Light engine rebuild questions

[jklnhyde]

I purchased a set of hi-comp 88mm pistons for my Paso, and although looking forward to getting work done right away, I would like some suggestions on what to do while I have the engine apart. The bike runs like a dream with the Weber setup, and it has less than 15k on the clock, so lower end work shouldn't be necessary. I do want a bit more oomph from the motor, but nothing obscene.
I have a Ferracci system installed and the Weber has no airbox, just an open oval filter.
Not looking to break the bank either...

Rick

[scimmione]

Adjustable cam pulleys (or offset keys) and a valve adjustment while the heads are off. I understand that poor valve timing will frustrate even the most experienced Weber tuner. That's going to be my next weekend project.

My guess is you'll need to spend some time with the Weber too once the engine is all buttoned-up.

Keep us informed, and take pics (please).

[Mc tool]

Good tip
I just spent ages making a piston stop,crank turner and dial gauge bracket .
I got
rear 24 - 66 , 270 duration , 111 lobe center
front 22 -70 , 272 duration ,114 lobe center
so there is a bit of adjusting to do . Ill set it up to have the intakes closing at 62 abdc.
Have you guys seen the article in the documents - general ... Paso cam timing

[Mustang505]

I have a Ferracci system installed

?? What is that?
Paso & Sport pistons were "hi comp" as standard 10:1. What are these you have bought?
Fast by Ferracci made 11:1 pistons and also 90mm 11:1 pistons.

[jayh]

Hi Rick, Just curious,if your bike is apart,what number is embossed on your weber pump cam ? .It might be helpful to others if you do get a chance to clean out your carby if you record and post the sizes of your idle jets,main jets air correctors and float level also, as not many webers 'run like a dream' ,as stock ,on a paso.I suspect that someone has had a tinker with it ,but I could be wrong.Hope you get a chance. Jay.

[paso750]

I wonder if he really should open his Weber if it runs so well, it may not afterwards.
If you wanted more oomph I guess you went the wrong way with the hi-comp pistons. A 785cc kit would have been the better choice. There´s not much you can do to get more torque w/o spending money. One thing would be aftermarket (torque) cams but those are not cheap.
Optimize what you have i.e. as it has been mentioned verify that ignition timing is spot on.

Everything else like bigger valves, exhaust, race cams etc will influence torque and specially power output but they will shift it to a higher rpm range which is not what you want.

What I liked a lot was the lighter flywheel. It doesn`t impact torque or hp but it makes the bike feel lighter, more vivid. (with lighter I don´t mean something like the ones from Nichols that are rather for race than for street use)

G.

[jayh]

I wonder if he really should open his Weber if it runs so well, it may not afterwards.

I'm not suggesting opening the carby with a sledge hammer,a flat head screwdriver usually works quite well on mine
Jay.

[paso750]

damn Jay. You should`ve told me before I tried to open mine
But did it never happen to you that you have an engine or some other part which was never opened, maybe covered by an old crust of oil and dirt which then just wouldn`t work as before or start leaking after proper cleaning, flushing or a complete rebuild ?

[jayh]

Yes on more than one occasion I have had similar problems,usually I can spot the burred off screws and bolts,before I start working on an item, a sure sign that king kong was a previous owner and tightened them until they became slightly loose again or substituted a 2 meter bar for a torque wrench.This is when the sledge hammer may become necessary.After 3 of the four retaining bolts snap and the fourth spins uselessly in its hole,take the sledge hammer and pulverise the item,sit down finish your beer and a smoke,then after picking up the shrapnel from all over the shed go inside and search ebay for a new one . Jay