Cone shovel running weak at operating temp.

[Guest]

My bike starts up fine, second kick every time. I'll go down the road for about 15 minutes with a great idle at stops and adequate power when throttling. My oil bag temp has been hanging around 200, and I am running a super e carb with a rubber band manifold, fiber glass spacers, and early o-ring heads with aircraft grade clamps. My idle gets erratic when at operating temp, but I don't have carb sneezes under load and it seems my bike looses power under load when warmed up and sometimes on a really warm day the oil bag temp climbs to 220. I am running lucas straight 70 in the summer and before my heads were rebuilt I ran a temp 180 in the bag.

I have checked my timing to make sure it didn't slip into full retard(know one should ever go there)
My pushrods are adjusted
I have compression (when cold)
My clutch isn't slipping when warm (drew a line to check for slip)
I jetted up just in case I'm running a bit lean but I still get and erratic idle and lose of power. I can get the card close to adjustment but then the bike will randomly snap off at a stop when idling, during which the bike is troublesome to kickstart when warm. I'm wondering if my guides are shot even though they are new cause the bike acts like it is losing compression when warm, plus I'm getting a bit of oil down in the chamber as evidenced by oily plugs........What is your guy's opinion?

[RetroRob]

Sounds like ignition to me, plugs, wires, maybe a coil going bad, a bad coil get worse when hot. Still could be timing. I worked on my super E all summer to get it dialed in, but most my jetting problems were mostly timing being off a little.

[Dragstews]

Get the motor up to temp and do a leak-down test, that needs to be out of the way....

If your loosing ring seal, all other work hunting down the problem will be in vain...

[FooDog]

My clutch isn't slipping when warm (drew a line to check for slip)

I am wondering, what does "drew a line to check for slip" mean? How is that done???

[Sky]

Ditto on the comp test, then a leak down. What are your comp numbers?
Are the rings new? oil o the plugs aint good. Rings, head gasket or guides...
Did you change compression by changing head gasket thickness or anything?
Solid or hydro and you sure they aren't adjusted too tight?
Running a phenolic spacer under that carb? Is that what you mean by "fiberglass spacers"?
What ignition? makes a diff on what to check for...

[panheadjess]

As previously mentioned, do the leak down test first, but if you don't find anything there, it seems like you might be too rich. Do you have to keep the enrichener on for a little while when it's cold outside (on the first start)? Possible ignition system problems too, of course. What size jets do you have in that carb? And what is the displacement of the engine?

[Guest]

Its an 80" motor with james fire ring head gaskets and 10:1 Wiseco forged pistons. All new seats and guides in the heads, and new rings that I staggered and gapped to factory spec. My super E was at a 68 main but I bumped it up to a 72 and a 295 on the idle. I do have to enrichen to start. I'm gonna chuck a new coil(it uses a dual fire, point ignition, copper wires) and rent a leakdown tester tomorrow, I totally forgot to even use one. I'll post the numbers as soon as I get them, thanks for all the help. The fiberglass "spacers" are in fact adapters to seal the rubber band manifold to the early style heads, I do need to get a rubber band style manifold as well. I'm running solid lifters, I will adjust them once again but I'm pretty sure they are spot on.

[Guest]

To add in regards to the oil leak: the heads are the "earlier" type with the cooling fins on top. The guides don't require guide seals and the spring retainers are original and would let me install them anyway. The guides were honed before assembly and the lack of seals may be contributing to this problem.

[panheadjess]

Jetting seems in the right ballpark, guess we'll see what the leak down tells us.

[panheadjess]

With points, if you don't get an answer with the leak down test, I'd look real hard at the condenser and coil.

[Pine18]

I have had a similar problem before and it happened to be a coil going bad when the bike reached running temp. Luckily I usually have a couple nos coils sitting around and are easy enough to switch out.

[BuxBitza]

I have had a similar problem before and it happened to be a coil going bad when the bike reached running temp. Luckily I usually have a couple nos coils sitting around and are easy enough to switch out.

I keep a coil, points, and condensor in my tool bag. I haven't ever needed any of them since converting to points, but they aren't heavy and Ilike having them.
Now back to the regularly scheduled thread.