Nov 12, 2008 · The YZ490 that Broc Glover rode in 85 was really close to a stock bike.He beat Dave Bailey on the trickest works Honda ever produced in the history of motocross.Glover is an amazing rider and the YZ490 couldnt have been all that bad. But I am not going to argue with someone that has owned one as I havent.

Feb 23, 2013 · My 1985 YZ490, now a 510cc was red and white new. I got this one done last year. motor balanced. Race Tech Gold valves, frame cut/ pulled back 0.03degs more than the 85 YZ250. rear shock drop relocated frame mount to 15mm. 226lbs Dry, 63.8hp rear wheel dyno. This bike has been reworked 4 times in it's life time and people at the track love my ...

Aug 20, 2022 · Please only provide (known to work) modifications and restoration techniques to improve the original factory/oem design of the YZ490. I own an 87 (T) model Can we start with head mods? I need some trade secrets from the masters, not the Eric Gorr fix that everyone can find on the internet.

Jan 18, 2011 · Myself, I always believed that Super Hunky (Rick Sieman, former editor of Dirt Bike magazine) was so hung-up on the first year YZ-490, the 1982 YZ-490J, that he put them all in the same piece-of-shit category.

Nov 13, 2013 · The best YZ490 mod I ever did was selling it and replacing it with something else lol. But seriously, the head mod, jetting, and adding a 10mm? section to the head pipe were the best motor mods. They were all in Yamaha wrench reports updates that they sent to the dealers back then. Unfortunately, I don't still have them, and I don't remember ...

Sep 17, 2008 · I have a 1984 YZ490 that I've had good luck with after I had the head reworked and lowered the compression etc. Well, I just broke an engine case and I would like to know if anyone could tell me what year engines will fit in my frame and what years will the internal parts of the engines interchange (including transmission).

Sep 19, 2014 · " yamaha yz490 (most years). Yamaha introduced the YZ 490 in 1982, after a solid run with the YZ465. Sadly, the 490 was heavier than the 465, nowhere near as reliable, horribly difficult to start (hot or cold), came with a grim suspension, vibrated enough to bring blisters to your hands and was impossible to jet.

Nov 28, 2016 · My 1985 YZ490/545 is a 38MM Mikuni off a 1982 YZ490 Bored Out to a true 38MM (Dial a Jet) sprayer for wide open throttle . 3.0 slid (cut 3mm off the face) 6 fj14 needle 35 Pilot . 340 Main @ 1250 foot elevation (needle position) 2 nd from bottom. 390 Main @ 500 Foot elevation (needle position) 4 th from bottom. Air Screw?

Aug 30, 2013 · The YZ490 motors were absolute BEASTS! The later years had considerably more power than was available in the first couple years. I think they finally topped out around 60-65HP in '89-90. Tons of torque, and a rip snarling mid-range hit that will lift the front wheel in just about any gear.

May 27, 2014 · I just got done rebuilding my IT 465 with a YZ 490 top end. Jetting wise I'm running a 45 pilot, and 420 main jet. I purchased a carb from eBay as a spare, and it was labeled as a yz490 carb but definitely seems like it came from a it …