Topic: CB350f slightly modded hot rebuild.

[IBleedHondaRed]

i have 2 '73 cb350f's. one was my first motorcycle that came from my granddad and the other was picked up in virginia beach early one summer morning headed to the oceanfront to go surfing. it was in a guys front yard and he wanted it gone. title in hand for free. figured that was a good price for a complete bike with a title and 8,000 miles. it had a blown head gasket and looked beaten by the weather. i also have 2 other engines i can use for parts.

i removed the engine and tore it down to the cases and labeled everything. im going to polish the covers up and painting the cases and other surfaces. i want to return the one my granddad gave me to stock, like it did when he had it and then cafe the other and rod it out a little.

i have no intention of winning races or building it for anything other than riding on a sunny day and my gf having something to ride when i ride my 71 cb500 cafe. but i do want to have some fun with it since im pulling it down anyways. i do not wish to bore it or do any head work to it but would like to do a new cam, oil cooler, electronic ignition and new 3 ohm coils as i robbed the coils to replace the ones on the other bike

plans:
1. Camshaft
2. All new oil and valve seals and engine gaskets (acquired)
3. Dyna S electronic ignition and 3 ohm coils
4. Oil cooler
5. Maybe new valve springs

Here are my questions
1. recomendations on WebCams grind #302 and grind #3 (requires new valve springs)
4. are there any kits out there for an oil cooler on these bikes or am i on my own?
5. would it be worth it to do new valve springs even on the #302 grind or am i over building the engine for my requirements?

any assistance here will be well received. its always good to get some other opinions before a build

[IBleedHondaRed]

do i need a new camshaft sprocket?

[Jerry Rxman Griffin aka MuthaF'er]

New/stronger heavy duty valve springs will help keep you from floating a valve into a piston head. If you don't miss a 1 to 2 powershift at redline you could be OK but I recommend replacing them for cheap insurance especially with a high performance cam. Been there done that.

[calj737]

no point in putting in a cam without/before doing head work. Air is far more beneficial than a cam. Possibly also less expensive and the cam ultimately relies on the valves/ports to feed the combustion. Good head work is the best $/# of performance you can get. Some of it, you can do yourself.

Get the head cleaned, lap the valves, check the seats and seals, guides, springs for any wear. Replace if necessary. Than grab a dremel and gently smooth out the ports.

Others will have to provide cam suggestions for the 350s.

[IBleedHondaRed]

i guess i was a little misleading there. i am planning on porting and polishing the head but i have no intention of doing oversized valves or getting a 5 angle valve job done. seats all look good, already have a package of new seals, and 3 sets of parts to choose from. looks like ill be salvaging 3 rocker arms from the other two engines

[IBleedHondaRed]

how about doing a regrind vs. a hardweld?

[Jerry Rxman Griffin aka MuthaF'er]

If you can buy a cam outright then don't waste your time or expense on regrind or hardweld. A cam is pretty much a cam. If you can't find a new cam then you can send in a stock cam etc and have those things done to it but it will probably cost you more.

[IBleedHondaRed]

was planning on using webcams as i am a dealer for them. you have to send them a core. will cost me about 225 for a hard weld or 140 for a regrind but then you have to adjust the valves to account for the difference. i have yet to see a company that sells them outright

Opinions on 3 ohm vs 5 ohm coils on the 350?

[SOHC4 Cafe Racer Fan]

I was going to echo the post about porting, but you have it covered.  With the port and polish and a cam, you should get an uptick in performance.  I think that your best gains will be to reduce weight as much as possible.  Strip the bike of anything that is not necessary, and replace as many heavy parts with lighter ones (replacing where possible steel with aluminum or other lighter materials).  If you can find an aluminum gas tank and seat, that should help.  Almost any fiberglass seat will reduce the weight, too.  I would also ditch the center stand and replace stock parts with mini-coils, aluminum rims, digital gauge, airbox, etc. to shed some weight.

[calj737]

Hard welds also need new rockers if I am correct. A re-grind or new stock cam might be all you need. A lot of $ for very little HP.

If you need 3 ohms! I have a brand new set. I installed them during my build, but then was told I need 5 ohm. They have 0 miles on them. Dyna 3 ohms, locally available.

[IBleedHondaRed]

How much we talkin here? and my other question is why did you decide you needed 5 ohm coils? i read the paperwork that came with dads dyna setup it says 5 ohm coils are recommended for points breaker ignitions.

[IBleedHondaRed]

pm me

[2strokeTrush]

get some pictures up, im in the middle of a 350f build to

[BCBarker]

you should be able to use a CB750 oil cooler adapter like these. same size as on the CB350F i believe.

http://www.cyclexchange.net/Oil%20System%20Comp%20Page.htm