WingmanEPTX

My Feedback: (1)

this is my first time taking apart a 4stroke. had to replace the bearings. its a saito 91...can anyone tell me how to re-set the timing when putting it back together?
help greatly appreciated!!!!!
-kevin

alfredbmor

The piston should be at TDC (Do not install the piston or rod just be aware that the pin tha moves the piston rod is at top), the cam gear have a dot which goes south, the very easier and fastest way is to use a x-acto knife to hold the timming gear when assembling.
There was a very good thread with a lot of pictures by Seamusg, but I could not find it. It would be a shame if it is deleted.
I have some pictures somewhere I will try to post later.

alfredbmor

Found it!!

http://www.rcuniverse.com/forum/m_76...tm.htm#7628750

I hope this can be of help for you, IMHO it is a very valuable thread.

w8ye

My Feedback: (16)

There seems to be a lot of things missed in that thread

If you remove (shake out) the intake cam follower on the 91, you can use the small end of a pushrod stuck down through the cam follower hole hole and into a oil hole that is in the intake lobe of the cam. This locates the dot on the cam at 6:00 for proper insertion in the engine when the crankshaft is at top dead center.

Which side of the connecting rod goes towards the front? If you look at the big end of the rod, the side that goes towards the crankshaft has a chamfer or taper at the very edge of the bearing hole. The side that goes towards the back plate is straight to a sharp edge in the bearing hole and the outer face of the rod has funny swirl marks where it rubbed against the back plate.

On the pushrods, the little end goes towards the top

Set the valves .002" - .004"

MetallicaJunkie

i read in another post when i was redoing mine about filling the cam housing with gear in it with warm vaseline then letting it cool with the gear in the right spot and it worked