aftermarket head?

[fullchoke]

I bought some ace 100 parts today and one of the engines has a head on it with a decompression valve. It is a bigger head with 2 extra fins. Was this aftermarket?

Thanks

[hodakamax]

Hey Fullchoke, send us a picture if you can, It sounds interesting and it does sound aftermarket.

Max

[fullchoke]

It has 15 fins. Could this be a super rat head that was tapped for the valve? Do Super Rat heads have 15 fins? I will try to get a picture soon.

Thanks

[Zyx]

Hard to say without a photo, but my Webco head came tapped for a compression release. Far as I know, none of the stock Hodaka heads were double tapped. There were other aftermarket heads around back then.

[taber hodaka]

Super rat heads were machined so you could tap and the head has a number stamped on it. The 90/100 racing head looks like a rat head but it does not have a stamped number and it is easy to identify.

[fullchoke]

I didn't see a number, but I didn't know where to look and it is pretty dusty.

Thanks

[fullchoke]

another question about the parts I got...one of the engines is an E engine. The cover that normally says "ace 100" says hodaka instead. Is this normal for an E engine? Purportedly this engine has never been run.

Thanks

[taber hodaka]

The bottom side of the head will have the numbers if there are any, send a picture if you ever take the head off. ---------Clarence

[Zyx]

E engines were accessory engines, sold as a complete replacement for 90's and 100's. The side covers from one engine fit several others, and I believe all 90 and Ace 100's would swap covers back and forth. I do not know specifically if the E engines were labeled Ace or just Hodaka since E engines are listed as replacements for Ace 90, Ace 100, and 100B. Perhaps because they were not exactly model specific replacements, they used the corporate logo instead of a model designation. Paul would probably know, as would some others who have been involved with Pabatco from the beginning.

The head in the photo looks like Hodaka, drilled and tapped for the release. Just which model would be hard to say, but I don't remember my 100B having a casting for drilling a second hole, so maybe Super Rat?

[DesertRat54]

Looks like someone put a Super Rat head on a stock Ace 100 motor. If it's never been run that way, that might be a good thing. I think the domes of the Ace and Super Rat pistons are different, so a stock Ace piston might not play nice with a Super Rat head. I recall that when Paul ran out of stock Ace pistons, he made clear that if you used one of his Rat pistons as a replacement, you shouldn't use the stock head with it. At least that's how I remembered it. If all this is true, it'd be interesting to see what type of piston is in there now.

Regarding the shifter cover, could it be that someone took a cover from a 125 and installed it in place of the stock cover? I recall that for motocross, the 1 up-4 down pattern was not a favorite with a lot of racers.

I like the Briggs and Stratton oil filler cap.

Bill in VA

[Dale]

The shift covers with "Hodaka" on them have a shift pattern of 1 down, 4 up. The "Ace 100" are 1 up, 4 down. The "Ace 90" are 1 up, 3 down.

The Hodaka and Ace 100 covers are interchangeable and allow you to change your shift pattern. Since the Ace 90 is only a 4 speed, it is not interchangeable. This is assuming that the Ace 90 transmission is the original 4 speed and has not been modified to a 5 speed...
Dale

[fullchoke]

Thanks guys for all the input and info. This engine with the decompression valve is not the E engine, it is a P engine that has been run, but all I know about it is that it turns over and feels like the compression is ok. The guy I got it from bought the P as a project and didn't know any history about it. I probably should have started a separate thread about the E replacement engine but I got both engines together and didn't realize the potential for confusion.
Greg