So just by chance, I keep ending up with good deals New Old Stock out of production MTC Engineering pistons for all my big bore bikes...
Now...
As luck would have it, I've stumbled into TWENTY sets available of New Old Stock MTC Engineering GS1000 74mm pistons for $250/set...
So I'm debating buying one or two sets of these MTC 74mm pistons. The price is right, they are a nice vintage high performance item, but probably not quite as good as a Wiseco. A $$ JE Pistons' set or $$$ Carillo/CP set would be lighter and run tighter bore clearances, but are both more $$$.
I have a GS1000 bottom, and several GS1100GK D-port head and 1074cc cylinders (head will get ported by Rapid Ray). Custom 1100E/G hybrid welded stroker crank built for a 1000 bottom, and a spare 1000 welded crank., an old MTC 1100E clutch basket, with CR31 (I have 2 sets) or CR33 (need to trade for some 33's?) carbs. Same Yoshi 265 duration .374"/.354" lift cams as my 750-920cc is getting.
This would put me at 1135cc and 10.65:1 (estimated, could mill domes slightly to lower CR for pump gas or retard timing when on pump gas).
Option #2 Wiseco 73.5mm K1100 kit (1120cc on my stroker crank) for $470
I have heard Ray talk about how Wiseco in his opinion are definitely better than MTC, and MTC use Old School Technology. I'm guessing the Metallurgy is better as far as expansion rates when heated, and the pistons are lighter. I am assuming.
Option #3 Custom Dynoman (JE Pistons?) 73.5mm gs1000 kit (1120cc for mine) $700
Definitely a higher quality piston than either of the other options. And higher price. Substantially.
Option #4 Dynoman (JE?) custom GS1100G 10.25:1 74mm 1135cc kit $675
This is a very sensible way to go because it brings the compression ratio down because it is made for the 1100 stroke which I will be running. The price of course is very high! Slightly less than the 1000 73.5mm pistons though for some reason.
Option #5 Wiseco K1085 73mm (1105cc for my crank) kit $470
This would leave the most metal in the 1100 block, heavier engine, but lighter rotating assembly , but it is only a 1 mm overbore into the 1074cc 1100 block!
I have been told by road-racers that the 73 mm pistons will spin up faster due to being lighter weight and less friction versus the 74mm pistons. I am not a drag racer, I may just for kicks do some land speed record type 1 mile airstrip drag races that the East Coast Timing Association, ECTA, puts on, but primarily I build all bikes for canyon carver or road racer type performance, and prefer tight tracks and roads. Lots of up & down accel/decel.
To be honest, this engine is probably going into a Rickman CR 900 chassis, which is quite a rare 1970s performance chassis kit, and will probably never see any really serious racing, but may, who knows. More exhiition/nostalgia build, bit I really do want it to seriously perform on all facets of its nature. It is not a bike that I would want to crash due to its rarity and cost to build. However, if I do end up getting heavily into vintahe heavyweight WERA Superbike racing, the engine might end up in a gs750 frame, or as I do have two welded cranks, might build two GS1000 74mm piston D-port head engines even! A GS750 based racer might get ridden and pushed very seriously... or better yet a Harris Magnum/F1 etc frame with this engine, I would be less hesitant to really really rip into it once my track experience had earned the right of passage to step up to the big liter+ bikes. Vs the classic and somewhat rare Rickman chassis...
Anyhow, I'm just looking for opinions on 73 vs 73.5 vs 74mm, and MTC vs the better choices. MTC certainly seems like the best choice as far as my budget is concerned.
74 MTC's & 74mm in general will be the heaviest piston. 73mm will leave me with lightest rotating assembly but more cast iron in the cylinders, so heavier bike overall (trimming weight everywhere possible on it).
73.5 sounds like a good compromise and leaves me with 1 semi-off-the-shelf overbore size if I were to ever put mega-miles on this engine (not likely in the Rickman frame).
Does anyone care to persuade me to sell some stuff off or work some more overtime out of dire necessity to get the better pistons?
Thanks GSR,
Chuck
Now...
As luck would have it, I've stumbled into TWENTY sets available of New Old Stock MTC Engineering GS1000 74mm pistons for $250/set...
So I'm debating buying one or two sets of these MTC 74mm pistons. The price is right, they are a nice vintage high performance item, but probably not quite as good as a Wiseco. A $$ JE Pistons' set or $$$ Carillo/CP set would be lighter and run tighter bore clearances, but are both more $$$.
I have a GS1000 bottom, and several GS1100GK D-port head and 1074cc cylinders (head will get ported by Rapid Ray). Custom 1100E/G hybrid welded stroker crank built for a 1000 bottom, and a spare 1000 welded crank., an old MTC 1100E clutch basket, with CR31 (I have 2 sets) or CR33 (need to trade for some 33's?) carbs. Same Yoshi 265 duration .374"/.354" lift cams as my 750-920cc is getting.
This would put me at 1135cc and 10.65:1 (estimated, could mill domes slightly to lower CR for pump gas or retard timing when on pump gas).
Option #2 Wiseco 73.5mm K1100 kit (1120cc on my stroker crank) for $470
I have heard Ray talk about how Wiseco in his opinion are definitely better than MTC, and MTC use Old School Technology. I'm guessing the Metallurgy is better as far as expansion rates when heated, and the pistons are lighter. I am assuming.
Option #3 Custom Dynoman (JE Pistons?) 73.5mm gs1000 kit (1120cc for mine) $700
Definitely a higher quality piston than either of the other options. And higher price. Substantially.
Option #4 Dynoman (JE?) custom GS1100G 10.25:1 74mm 1135cc kit $675
This is a very sensible way to go because it brings the compression ratio down because it is made for the 1100 stroke which I will be running. The price of course is very high! Slightly less than the 1000 73.5mm pistons though for some reason.
Option #5 Wiseco K1085 73mm (1105cc for my crank) kit $470
This would leave the most metal in the 1100 block, heavier engine, but lighter rotating assembly , but it is only a 1 mm overbore into the 1074cc 1100 block!
I have been told by road-racers that the 73 mm pistons will spin up faster due to being lighter weight and less friction versus the 74mm pistons. I am not a drag racer, I may just for kicks do some land speed record type 1 mile airstrip drag races that the East Coast Timing Association, ECTA, puts on, but primarily I build all bikes for canyon carver or road racer type performance, and prefer tight tracks and roads. Lots of up & down accel/decel.
To be honest, this engine is probably going into a Rickman CR 900 chassis, which is quite a rare 1970s performance chassis kit, and will probably never see any really serious racing, but may, who knows. More exhiition/nostalgia build, bit I really do want it to seriously perform on all facets of its nature. It is not a bike that I would want to crash due to its rarity and cost to build. However, if I do end up getting heavily into vintahe heavyweight WERA Superbike racing, the engine might end up in a gs750 frame, or as I do have two welded cranks, might build two GS1000 74mm piston D-port head engines even! A GS750 based racer might get ridden and pushed very seriously... or better yet a Harris Magnum/F1 etc frame with this engine, I would be less hesitant to really really rip into it once my track experience had earned the right of passage to step up to the big liter+ bikes. Vs the classic and somewhat rare Rickman chassis...
Anyhow, I'm just looking for opinions on 73 vs 73.5 vs 74mm, and MTC vs the better choices. MTC certainly seems like the best choice as far as my budget is concerned.
74 MTC's & 74mm in general will be the heaviest piston. 73mm will leave me with lightest rotating assembly but more cast iron in the cylinders, so heavier bike overall (trimming weight everywhere possible on it).
73.5 sounds like a good compromise and leaves me with 1 semi-off-the-shelf overbore size if I were to ever put mega-miles on this engine (not likely in the Rickman frame).
Does anyone care to persuade me to sell some stuff off or work some more overtime out of dire necessity to get the better pistons?
Thanks GSR,
Chuck
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