Topic: RC ENG 1160 big bore kit questions

[teebee67]

Some of you may remember I blew my race engine up and have now stripped the engine from a project bike. Found it to have a RC Eng 1160 kit fitted which seems in good condition. I am trying to get this ready for a meeting on the 21st so haven't much time. It appears to be fitted with an F2 head, has 34mm inlet and 30mm ex valves though it appears to have a standard cam and standard valve springs. I have a mild race cam (Cycle X CX3 which is a Web Cam 63A grind) and I have new Kibblewhite springs with titanium top collars. These were all for a K head, would I be OK to use them in the F2 head ?
The barrels are fitted with Cooper rings (Wills rings) and had a cut away gasket sort of loosely outside the Cooper rings (there is no gasket between cylinders and some of the studs stick through half a hole in the gasket - if that makes sense to you). Does anyone know where I can buy cooper rings and a properly modified head gasket ? Alternatively should I remove the Cooper rings and fit a copper head gasket of the right size, it is 73mm bore?
Any help greatly appreciated.

[Jerry Rxman Griffin aka MuthaF'er]

Cometic for the gasket. Standard, Copper or MLS.

[jaguar]

1160?
so a stroker motor?

[teebee67]

Thanks Jerry.
Yes it's a stroker motor.

[cbr954]

You cant use K retainers on F2 valves as the keepers are a different angle.  The springs should work though.  If the cylinder was grooved for copper rings then you have to use those plus the copper gasket, the MLS gasket wont work.  Dynoman has copper gaskets.

[bear]

Tony,

Try Atlas Gaskets in Berkshire.   
They should be able to help you out with the gasket and o ring wire.

If you are really pushing for time try annealing the gasket, not best practise but beats missing out on a race meeting.

Can I make a suggestion?
Your stroker motor will hit the top of it's torque/Hp curve at lower revs.
So I suggest you consider adjusting you shift points down the rev range a little.
We usually add about 5deg advance one the suggested cam timing for our motors.

Cheers,
Brian

[johno]

Bear,
Only have to advance the valve timing if your over 6 foot and more than 100kg 

[teebee67]

Thanks for the info guys, I will be contacting Cometic and Atlas. What about the possibility of removing the Coopers rings and running with a copper head gasket - any thoughts on this as it is the easiest and quickest option ?

Interesting about the cam timing. By mistake I ran the cam a little advanced on my 850c (I set the correct advance at .040"lift (British practice) instead of .050" (American practice) result was it pulled like a train low down but peak power (86 bhp rear wheel) was at 8600 rpm. Had real good torque too- around 74  ft/lbs if I remember correctly.

Regarding the keepers, can I take it that the ones with the Kibblewhite titanium top collars, which I bought for my K head but haven't used, are not suitable for the F2 head either?

Thanks again for the help and info.   

[bwaller]

The O-rings are used for extra pressure sealing. I find new copper head gaskets to not be "dead soft" so anneal them automatically. With a soft copper gasket and O-rings in place the gasket squishes embedding the ring. I like to order the bore of the gasket slightly undersize then remove material to fit the bore correctly. Also after having tried different materials including Copper Spray etc. I prefer a sealer called Gasgacinch to help seal the copper gasket. A little dab'll do ya. This combination has worked very well in mine.

[MRieck]

I have decked an copper o ringed cylinder flat. Ready to use an MLS head gasket now.

[bear]

Bear,
Only have to advance the valve timing if your over 6 foot and more than 100kg 

OY! enough of the fat jokes Johno.

Cheers,
Brian