Finished my 1977 Yamaha IT 400 D

[ggundamblue]

its so freakin hard to kick!! i bought it and it had no compression and now its got it off the a$$ any idea's? i did a top end rebuild...im just disapointed :( ...i spent over 450 in parts tryin to fix it...so any help would be nice. thanks!

 

[Moparman1539]

Help with what? Does it still have compression? Its a 400cc dude, it going to be hard to kick.

 

[ggundamblue]

no the fact is i've been kicking it for 3 hours and still no start. i've tried jump startin it still nothing..

 

[Moparman1539]

Check and make sure you got gas and spark. (the three main things are Gas, Spark, Compression) did you put in a new spark plug? Maybe the jets in the carb are clogged, clean out the carb.

Does it have spark? what does it do? do you smell gas? does it try to start? is your leg tired?!?!

the more info you give the more help we can give back.

 

[laynbodys-10z]

i got a yz 490 and it was almost impossible to start until i figured out u have to make sure its at the top of its stroke, then kick it over and it would fire up first or second kick

 

[ggundamblue]

top of the stroke? does that mean make the piston stop at the top of the cylinder? im cleaning out the carb tomorrow...idk someone said check the timing but i doubt its that..i did put in a oversized piston in it because the last person who had it burned up the old one and ya. haha. its got about 150psi of compression good spark and i smell gas on the spark plug. mixed the gas and oil to 16:1 for the break in period...it wont even start when i try and push it really fast and hopon and put it in gear. it studders and the back wheel locks up and it makes me stop which makes sense to me...

 

[colby72olds]

it's going to be very hard to push start a bike with that much compression.
yes, TDC (top dead center) is when the piston is at it's highest point.
It's probably not the timing, are you sure you have spark?
snap your plug in the boot (with it out of the head) and kick it, see if you can see the spark. If you do, it's more than likely going to be the jets clogged.

 

[rmc_olderthandirt]

it wont even start when i try and push it really fast and hopon and put it in gear. it studders and the back wheel locks up and it makes me stop which makes sense to me...

Unless you are on a hill that approach probably won't be succecssful.

What gear are you putting it in when you try this? If you drop it into first then I would expect the rear wheel to lock up and just skid. You might have better luck if you try 2nd gear.

Better yet, take it to the top of a hill or pull it behind a quad or something. Get it rolling, shift to 3rd gear and let the clutch out.

 

[N3WFI3]

ya 3rd gear is best for bump start

 

[Coop]

Better yet, take it to the top of a hill or pull it behind a quad or something. Get it rolling, shift to 3rd gear and let the clutch out.

I hope someone takes pictures if you try this quad technique :).

My guess is a dirty carb and/or fouled plug. That is if you are sure the top end is done correctly.

 

[Kwakasaki]

If its the same 360/400 head I know from the mid 70s yamahas, you have two plug ports on it. I always ran a decompression valve on one of the plug ports. Worked great when trying to kick it over and especially when you were trying to stop the monsters with those lovely drum brakes. :yikes: