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1990 yz490

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Well I really don't know where to turn I've searched all over the net and can't find info on this thing I wish I had money to pay for a clymer for it but I don't lol sorry for rambling but the problem is I need to know what my float height should be and what else I should look at as the bike will not idle at all and doesn't seem to have the power it should everyone says there so scarry lol I'm only 165 lbs. And mine won't pop a wheelie with or with out the clutch in any gear past second and doesn't seem to be revving out as far as it should it has a fmf gold series expansion chamber and a fmf power core 2 tip and boyseen power reed I'll have to get back to you on what jets it has also I would like to know what air filter this bike uses I just took the seat off and air box is empty no brackets nothing what would I need to filter this thing again lol

Edited by yz490noob

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If your motor has more than 50 hours on it, you first off need a new piston and rings

You can download manuals for free on line.

Don't change any jetting until you replace all worn out motor parts

- reeds

- piston

- rings

- plug

 

If it has been running without a filter for more than 10 minutes, the entire top end will need to be replaced......

Edited by TheKoolAidMadeMeSick

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Thanks for the link but I can't seem to get it to load up and this bike is on a fresh rebuild compression is good and it's running rich even missing the filter lol

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Maybe clean the petcock ? My CR won't run rite until I clean that out. If you YZ has a mettle tank or anything that can rust you can clog up the petcock. Hope this helped

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