New Rider
Currently Offline
Posts: 44
Likes: 0
Joined: Oct 22, 2013 20:48:07 GMT -5
|
Post by stevo on Oct 24, 2013 6:08:54 GMT -5
Installing 80cc bbk.I've been. down three weeks!!!!.first i had no compressionyhen i bent a valve.now i am being told thatt. it is my rockers?  ?, |
|
Currently Offline
Posts: 0
Likes:
Joined: May 3, 2024 3:56:01 GMT -5
|
Post by Deleted on Oct 24, 2013 6:28:26 GMT -5
Let me guess....it ran fine until you started mucking with the stock 50 right?
|
|
Sophomore Rider
Currently Offline
Posts: 211
Likes: 1
Joined: Aug 7, 2013 1:36:49 GMT -5
|
Post by f4milytime on Oct 24, 2013 13:47:26 GMT -5
Top end rebuild, That's what I'd do just to recheck everything. 0.02 ALOHAS & Good luck By the way welcome to the forum !!!
|
|
|
|
Post by jjoshua20213 on Oct 24, 2013 15:05:38 GMT -5
If you had no compression followed by a bent valve that means you didn't time the camshaft with the flywheel correctly and the piston hit the valve. Its possible it could have caused damage to the rocker arms too. Check piston for damage as well as valve. A bent valve will look visibly bent. Put it back together, time camshaft with flywheel. Inspect for further damage, adjust valves. Then turn the engine over with your hand first (Spin flywheel) and make sure nothing hits. Then try to start it.
|
|
|
|
Post by urbanmadness on Oct 24, 2013 20:33:33 GMT -5
Always run and engine thru 4 or 5 revolutions by hand after you've put it back together, then check the timing marks again, just to be sure. Nothing worse then being a couple of teeth off on the cam timing... or worse, bending valves by being way off.
You'll get it right, just keep at it... I'd replace the head, piston(if damaged), rings and rockers just to be sure. Take your time. At least the parts are cheap.
|
|
|
|
Post by teddy554 on Oct 24, 2013 20:39:19 GMT -5
If your scooter was a 64mm valve and installed a 69mm valve head with bbk or vice versa you can cause a bent valve with the wrong rocker arms There are short and long rocker arms one for the 64mm and one for the 69 they wont work right for each other, if you put your stock head back on with the stock rocker arms should work fine after
|
|
|
|
Post by teddy554 on Oct 24, 2013 20:42:53 GMT -5
|
|
New Rider
Currently Offline
Posts: 7
Likes: 0
Joined: Aug 13, 2013 0:10:08 GMT -5
|
Post by chase50 on Oct 26, 2013 18:33:50 GMT -5
I'd be very surprised if you bent a rocker arm... they're strong as heck! I did something similar when I installed my BBK. I replaced the valve that I bent and everything was perfect.
|
|
|
|
Post by alleyoop on Oct 26, 2013 18:42:37 GMT -5
The question is why did the valve get bent? That is what should be addressed and what NOT to do and or check before trying to start a motor.
Alleyoop
|
|
New Rider
Currently Offline
Posts: 44
Likes: 0
Joined: Oct 22, 2013 20:48:07 GMT -5
|
Post by stevo on Oct 30, 2013 20:54:47 GMT -5
Thank u everyone! I tried to take that ex bent. valve out .it is in there boy,that is not coming out.I welded the 64 rockers to thr shaft and stressed cracked them.Valve will not come put
eeeeerrrrrrggghhhhh.
|
|
|
|
Post by millsc on Oct 30, 2013 21:28:14 GMT -5
Easier to get a new head I have several both valve length I'd sell very cheap cost me ten bucks to ship it so I'd sell it for 15 25 bucks total
|
|
New Rider
Currently Offline
Posts: 44
Likes: 0
Joined: Oct 22, 2013 20:48:07 GMT -5
|
Post by stevo on Oct 31, 2013 12:44:20 GMT -5
Thank you! I do need a head
|
|
|
|
Post by jjoshua20213 on Nov 4, 2013 9:21:23 GMT -5
|
|
|
|
Post by millsc on Nov 4, 2013 14:09:50 GMT -5
|
|
Sophomore Rider
Currently Offline
Posts: 114
Likes: 0
Joined: Feb 24, 2013 10:04:01 GMT -5
|
Post by dude on Nov 6, 2013 1:24:45 GMT -5
For the price a good kit just pull the vavles out. Use a a dremel to clean up the ports then hand lap the vavles in. |
|
main jet
..BAD TO THE BONE..
