The Hodaka Club Forum

Hi everyone, I recently bought a small lot of parts and I need some assistance Identifying this cylinder and head. Among the parts in this lot that I have identified is model 98 cases and cylinder which is what I was looking for. I am unsure if this head is for a model 98. I am also unsure what model this 125 cylinder fits. Exhaust port to top of cylinder is 29mm. Thanks!

Adam

Looks like a Model 95 head with a 7 scratched over the 5. I would get the cylinder measured. The 95/97 cylinder is a 125 (123cc).

The Model 98 is a 100 (98cc) Super Rat. They were Sunkist looking & had the same gas tanks. The 98 motor was also painted black while the 97 motor was aluminum colored.

The Model 97 Super Combat cases number will start with the letter “K” and the Model 98 Super Rat cases start with an “L.”

Go carefully and determine with accuracy what you have! Victor

Standard Combat Wombat cylinder should measure 28mm (top of exhaust to cylinder head deck). NOTE: CW cylinder is piston port induction with a "Victory Port" (boost port, above the intake port which is NOT directly directly connected to the intake port) . . . i.e. the "ceiling" of the intake port passage has no holes or direct connection to the bottom of the "vee" of the Victory Port.

The standard Model 03 cylinder measures 30mm (exhaust to head deck) and is reed ported (i.e. there is no "ceiling" in the intake port passage).

Finally, standard SC(Model 97) measures 26mm and is reeded.

Ed

PS: I can't be sure, but the bottom photo looks like a Model 03 combustion chamber shape. The "7" Vic mentioned looks to me like a shiny edge on the blank number block from some scraping to clean the area. The Model 95 head has a "5" molded in that location. All other heads for alloy cylinder Hodie 125cc engines have a blank at that location - which makes them harder to ID (as you are finding out).
Ed

Look more closely Ed, zoom in. The 5 has several lighter vertical scratches but the top and right edges are scratched more heavily. At least that’s what I see…. Victor

I see what you mean Vic. Researching more.
Ed

That is an 03 Wombat cylinder and head......100%.

Danny

All the late model heads had the second digit blanked. Same head casting for the mdl 97,98,99 and 03 Wombat.

03 Wombat was the only Hodaka with that intake port arrangement.

Danny

Having second thoughts about the cylinder head. Head might be from a late model 100. Easy enough to find out. Measure combustion chamber diameter.
125 = 56mm.
100 = 50mm.

Danny

Following a review of the play, the call on the field is reversed (both calls that is). The head is NOT a Model 03 or a Model 95.

The cylinder head in the photo above is clearly a 100cc head. I'm not sure which model, though it is certain it is for an alloy cylinder 100cc Hodaka.

I managed to find a stock Model 99 Road Toad head. Following careful measurement of features (distance between stud holes, OD of sealing groove, OD of apparent bore, etc) and calculation of ratios of those sizes. I then did the same measurements and ratio calculations using a large print out of the cylinder head photo. The two heads are a "match" - so the head in the photo is a 100cc head.

NOTE: The "blank" in the 2nd digit location of the molded-in part number on the actual head I measured, has a rounded bottom edge and the "vertical" ridges which can be seen in the photo.

Ed

Great info everyone, thank you! So I measured the combustion chamber on the head and it’s a little over 50mm across. Will this head work on a mdl 98 super rat? Also is there a good place to buy/sell/trade used parts? I don’t need the model 03 cylinder.

While that head will indeed "bolt on" to a Model 98 Super Rat . . . it may not be the right head for the application. If it is from a Model 99, 01 or 02 you'll end up with low cranking compression.

Ed

While were at it could I get some help with these parts are they are they not hodaka part's

The 2 pieces on the right appear to be a spark arrestor for a Road Toad style exhaust pipe. The two pieces bolt together. The little diffuser on the bolt is aluminum. And it will melt if not removed prior to a fire cleaning session...

thanks dale , these came with a pile of parts i dragged home .....albert