Hi,
Anyone tried lighter crank flywheels or stator ?
Would it make the engine more difficult to manage on the throttle ? The engine just seems so heavy for a small 500 2 stroke and I wondered if there was somewhere that some weight could be lost - perhaps all components are just that little bit heavier than in a modern engine and it all just adds up to it being heavier than expected ? Where does an RG500 save its engine weight compared to the RD500 ?
Thanks.
Cheers
Paul
Lighter Crank Flywheels / Stator ?
Moderator: rztom
Re: Lighter Crank Flywheels / Stator ?
Hi Paul, we machined the fly wheel down I think was about 3 ounces in weight. It's on the bike running haven't ridden it yet.
First saw pictures of this done in Japan.
Cheers Ron.
First saw pictures of this done in Japan.
Cheers Ron.
Re: Lighter Crank Flywheels / Stator ?
I used to race a 350YPVS. It had a lightened flywheel like that. It certainly was one of the fastest on the grid. No down side as far as I could tell.
Current Bikes
1984 47X RD500LC, 2018 Triumph Speed Triple RS, 1999 Honda CB600F Hornet
Past Bikes Include
RD250LC, RD350YPVS LC2 Race Bike, RD350F2, 1976 CB400F
1984 47X RD500LC, 2018 Triumph Speed Triple RS, 1999 Honda CB600F Hornet
Past Bikes Include
RD250LC, RD350YPVS LC2 Race Bike, RD350F2, 1976 CB400F
Re: Lighter Crank Flywheels / Stator ?
I have used a Motoplat ignition on a 350LC and that had a small/minimal flywheel, which was tiny when compared to stock. Ran great, but no charging capability...
With the RD500 crank geometry and their relatively high polar inertia, I would suggest that the stock flywheel is almost superfluous, apart from ignition/charging purposes. Got to be wary of harmonics/dynamics though....
Re. the overall high engine mass, losing the cast iron liners, going to separate heads, plastic cases (like LH TZR etc), maybe electric water pump, smaller clutch, etc, could result in 15+ lbs reduction in weight.....
With the RD500 crank geometry and their relatively high polar inertia, I would suggest that the stock flywheel is almost superfluous, apart from ignition/charging purposes. Got to be wary of harmonics/dynamics though....
Re. the overall high engine mass, losing the cast iron liners, going to separate heads, plastic cases (like LH TZR etc), maybe electric water pump, smaller clutch, etc, could result in 15+ lbs reduction in weight.....
Re: Lighter Crank Flywheels / Stator ?
Thanks for the info everyone.
It sounds like making the engine lighter could be a really big project all on its own.
Cheers
Paul
It sounds like making the engine lighter could be a really big project all on its own.
Cheers
Paul
Re: Lighter Crank Flywheels / Stator ?
The RZ's clutch is massive. I have heard it compared to the TZ750 clutch and the RZ Tranny is more robust than the RG as witnessed by necessary upgrades needed to improve longevity on the RG. 2 areas that are hard to reduce weight. I don't know about the cylinders. Regardless of liners which the RG has the same issue, the next generation unlined 2 stroke barrels had far less extra casting in comparison. More Port area and less wall thickness and larger cooling passages. Example TZR 3xv VS RZ500
YPVS, arguably the best of the exhaust tuning designs, is probably heavier than other designs as well.
YPVS, arguably the best of the exhaust tuning designs, is probably heavier than other designs as well.
1985 RZ500
1986 RG500
1986 RG500 C
1992 RGV500 WW ATR
1992 RGV500 LS
1985 NS500 Spencer p
1989 TZR500 Biaggi p
1984 RZV500 Rainey p
1994 NSR250sp R
1983 NS250 p
1987 RG250 WW p
1983 RG250 p
1988 YSR50 p
1986 RG500
1986 RG500 C
1992 RGV500 WW ATR
1992 RGV500 LS
1985 NS500 Spencer p
1989 TZR500 Biaggi p
1984 RZV500 Rainey p
1994 NSR250sp R
1983 NS250 p
1987 RG250 WW p
1983 RG250 p
1988 YSR50 p
Re: Lighter Crank Flywheels / Stator ?
The first and easiest measure to reduce engine weight is to remove the balancer crank and these anti- lash gears on the primary drive gears ( not sure if this is the right term). I run 3 RD500 engines without balancer crank and have no issues with vibration.
Re: Lighter Crank Flywheels / Stator ?
I always wondered about the balance shaft, None of my bikes run the anti-lash gears, But I always wanted to leave out the shaft, It was the thoughts of stripping it back down if it went to shit that put me off.wolfgangh wrote: ↑Sat Jul 18, 2020 5:00 pm The first and easiest measure to reduce engine weight is to remove the balancer crank and these anti- lash gears on the primary drive gears ( not sure if this is the right term). I run 3 RD500 engines without balancer crank and have no issues with vibration.
Any difference in vibration
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1989 VFR750R RC30
1984 GPZ750 Turbo
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1989 VFR750R RC30
1984 GPZ750 Turbo