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$1500 - 1992 Yamaha WR250ZD Sumo/Roadrace Project Kit
No title as Maine doesn't title below 300cc, bill of sale as is where is.
The Bad: Since the last rebuild as a +6mm 292cc overbore, I've been chasing an issue where in 4th and higher, sustained WOT it starts to detonate, then cuts out like someone hit the kill switch. I've been monkeying with jetting, verifying solid fuel flow, etc, but am hampered by the small issue of not a lot of places to test changes to see if they help. Last thing I did was retard the timing by 2deg but haven't had an opportunity to test. I suspect that big old Wossner piston in there is causing enough vibration that at sustained WOT under load (road gearing) it's foaming the fuel in the bowl preventing it from refilling properly. If you let off, coast for a min, then smack the throttle it'll pull like a freight train for a bit before doing it again. On the flip side at a track like Boxshop, I don't go past 3rd, no issues. Lack of opportunities to use it, test it, etc means I haven't ridden it in a couple years now. If it sits, it's just taking up space so time to go.
The Good: This bike has been down to a raw stripped frame, straightened by PK and built back up. It's solid. Frame has been powdercoated, engine has 22hrs on the top end, 36hrs on the bottom end. Clutch pull rod isn't ragged out, clutch pushrod stack shimmed to perfection, exhaust is mint, has a YZ swingarm and 09 YZ450 forks, two sets of RAD sumo wheels that have been rebuilt with Dubya heavy duty spokes, 38mm SmartCarb that makes this bike behave better than EFI four strokes, it's all there. The motor is very un-twostroke like, linear power from idle up with no 'hit' or spike, it's like a ripper Honda aircooled four stroke single. (Kick it like a big four stroke also...) At Boxshop it'll hang with modern 450s. The only bike that I've ridden that can match it on pavement at Boxshop was a TM, this bike LOVES to be on it's side carving. Handled awesome at Canaan as well. For Sumo, I think it's setup to be slightly 'too' stable?
RAD Sumo wheels
Beringer 6 piston front brake with matching master and 320mm GoldFren full floating rotor
09 YZ450 forks setup by PK in custom 10mm offset RSW Racing billet clamps
YZ250 fuel tank
GPTech aluminum radiators, silicone hose kit
Boysen engine covers
FMF Fatty chamber, Pro Circuit 304 muffler
Kustom Kraft +6mm ported cylinder and head
VForce 3 reed block
38mm SmartCarb
OEM shock rebuilt and revalved by Factory Connection
Seat redone by Ceet
Spares:
Additional OEM seat
Lots of random plastics
Gaskets/seals/oh boy
Additional set of RAD Sumo wheels
OEM forks/brake master/caliper
Spare OEM shock
Penske shock valved for road racing by PK, needs front end shortened to match if going to run it
Needles, float bowl, etc for the SmartCarb
1994 cylinder (the 'hot' cylinder for this generation) and head suitable for repair and replate if going back to stock or +2mm (262cc) bore
New exhaust valve - Needed if going back to stock or +2mm, stupid hard to find in unworn condition