Topic: What should I do with my head?

[edwardmorris]

So I've been working away on my project as I'm able to find time and some of you incredibly great guys have been helping me out in my build thread -> Thank you!

I got to the part where I took the engine apart and found that the bike was running HD springs with a Web Cam 41-a, ALL threaded holes for the rocker arm assemblies as well as the valve cover have helicoils in them, several of them have stripped past the helicoil as well. The pistions, rod, studs, pretty much everything else is stock. I was suggested either upgrading to a racer or finding stock springs and cam and keeping to my stock theme. I do want to keep it stock but having terrible luck finding stock springs for a K2. I took it apart, and found that two of the valves are bent and its possible that the guides are bad too (don't have an inside gauge). The local machine shop wants nothing to do with anything that came off a motorcycle and shipping away parts for work is just getting expensive too quickly.

• Are there stock spec replacement springs and valves I can buy somewhere?
• Can I keep the web cam 41-a with stock springs or find an OEM one?
• Should I go with new brass guides as well? 70cb750/Prokop here installed them himself, so I know I don't really need a shop to do this.
• The threads where the helicoil is stripped, can a new coil be dropped in? I want to avoid drilling anymore to install time-serts, but will do if I have to.
  

[Ace]

Here is the address for Web cam shafts. Stocks springs are ok so the website says.

http://webcamshafts.com/index_blank.html?pages/vehicle_search.html

You can still buy stock springs from places, about $22 (Yamiya750) for both inner and outer plus postage. Or you could buy some on ebay or a new head with valves and springs and see how you go.

Valves and guides, bronze guides and get some aftermarket valves. APE or cyclex come to mind and I've used both their products, not complaints.

Guides you can do yourself, need to cut the seats afterwards.

As for the helicoils, post a pic so we can see. If you remove the helicoil and the threads look ok, you can either put in a new one or tap the hole out again making sure it is good and put another one in. On assembly, torque down to spec and never over tighten which may have happened by the PO.

If money is an issue, save up as you don't want to skimp on a part and have it fail later on and cause more $$.

Good luck.

[edwardmorris]

Here is a pic

[Whaleman]

I have a stock cam and stock springs you can have for the shipping. Dan

[PeWe]

I cannot see the small inserts in the 2 holes for the oil lines leading into the cam towers.
'oil control orifices'
12238300010

Important small parts to ensure oil pressure to cam, rocker arms

[edwardmorris]

I cannot see the small inserts in the 2 holes for the oil lines leading into the cam towers.
'oil control orifices'
12238300010

Important small parts to ensure oil pressure to cam, rocker arms

Have those fortunately, and all 4 o-rings bagged and tagged.

[KayOne]

Hi Edward. Something you may want to consider when considering your options with this head.....I'm pretty sure the head is not a K2 head as evidenced by the lack of 4 fin supports as viewed from the side. Also the early heads have slightly different fin contours front and rear.

That being said, I don't know how important being 100% correct means to you. There are many nice restorations that have a mixture of early and late parts.

Not trying to put a damper on your build. You are making great progress!

[edwardmorris]

I have a stock cam and stock springs you can have for the shipping. Dan

PM Sent.

[edwardmorris]

Hi Edward. Something you may want to consider when considering your options with this head.....I'm pretty sure the head is not a K2 head as evidenced by the lack of 4 fin supports as viewed from the side. Also the early heads have slightly different fin contours front and rear.

That being said, I don't know how important being 100% correct means to you. There are many nice restorations that have a mixture of early and late parts.

Not trying to put a damper on your build. You are making great progress!

Oh draaats. I was being a stickler for correctness, guess I should just start looking....unless I make this one work.....so frustrated

[HondaMan]

Hi Edward. Something you may want to consider when considering your options with this head.....I'm pretty sure the head is not a K2 head as evidenced by the lack of 4 fin supports as viewed from the side. Also the early heads have slightly different fin contours front and rear.

That being said, I don't know how important being 100% correct means to you. There are many nice restorations that have a mixture of early and late parts.

Not trying to put a damper on your build. You are making great progress!

Oh draaats. I was being a stickler for correctness, guess I should just start looking....unless I make this one work.....so frustrated

Other than the damaged parts, there is no big reason it won't work. Stock springs and cam will go a long way toward preventing future problems, too. You might be able to find a K0-K3 head for cheap, though? The last one I bought was $50, just needed new guides and a valve job, became brand new.

[edwardmorris]

Other than the damaged parts, there is no big reason it won't work. Stock springs and cam will go a long way toward preventing future problems, too. You might be able to find a K0-K3 head for cheap, though? The last one I bought was $50, just needed new guides and a valve job, became brand new.

I guess I'll go for a proper head, and sorry for double posting, will the current rocker arms, cam, basically everything under the valve cover still work on an actual K2 head?

[HondaMan]

Other than the damaged parts, there is no big reason it won't work. Stock springs and cam will go a long way toward preventing future problems, too. You might be able to find a K0-K3 head for cheap, though? The last one I bought was $50, just needed new guides and a valve job, became brand new.

I guess I'll go for a proper head, and sorry for double posting, will the current rocker arms, cam, basically everything under the valve cover still work on an actual K2 head?

Yep, sure will. Those parts fit all the heads. Only the F2-3 heads with their different valves and springs changed over the years, as far as fit goes.

You might find the "real" K2 head uses smaller O-rings around the oil jets and the other end of the rocker towers, but that's not hard to solve. These came in 2 sizes over the years.

[KayOne]

No worries Edward. I was in the same boat with my K1, it had a late model head and cylinder. I purchased a very nice  KO head and cylinder from a SOHC forum member.

On a positive note, according to Hondaman, the earlier heads have better guides. Mine have so little wear that the head requires no guide replacement or machining. Maybe you will luck out and find a decent head for less than all the parts and expensive machining your head may require.

[edwardmorris]

Thank you guys, I'll find one and set this one aside. In the meantime, I will check out the crankcase as Hondaman so clearly explained in my build thread to try and make sure this never happens again.