gerald m

Engine is 86-13b na I am in the process of building engine mounts for my bike build and was just wondering if anyone has had problems with the center iron breaking out around on in the engine mount holes while under extreme pressure? . ( not just a daily driver but something that is used for racing etc.) ..

On the right hand side there are two smaller bolt holes on the bottom of the end irons one on each side .. Can these holes be drilled larger and deeper for threads without fear of going into the water jackets or would I just be drilling into the bottom end oil area ?

Also I should know this but is there a reason for the studs being used on the engine mounts in stead of bolts besides making it easier to line things up and maybe keeping people from bottoming the bolts out and causing problems ? The way I am building things there is no room for the studs to be used as the mount plate fits flush against the mount area . pic attached . I would also like to use the lower power steering mount hole and maybe the two in the front aluminum housing where my crooked old fingers are pointing . thanks Gerald m

Aaron Cake

iTrader: (1)

Never heard of the center iron bolt holes breaking under any circumstances.

The front iron studs are for the accessory brackets. Due to the much thinner casting of the front iron in that area, I don't think I'd want to use them to mount the engine. From memory there's about 1/2" room to drill them out, but holy hell, please measure before you do.

Have you considered using the front cover from an older engine? The older engines mounted via a crossmember on the front iron. Might be easier.

BLUE TII

iTrader: (9)

I have cracked two center irons on my motor but on the forward hole of the two outside motor mount holes on the intake/exhaust side of the motor opposite of what you are asking.

I think it must be because my torque arm from alternator mount to passenger side strut tower somehow magnifies the force/vibration into this location.

So, if you do add/alter mounting points- make sure you don't make matters worse as I had apparently done.

gerald m

Well I know better than to doubt what you say Aaron , I think I will stick to the center iron and the lowest hole on the front iron seems to have a fair amount of meat around it ..
The SPARK PLUG side I am not to concerned about as it faces forward and actually torques down against the frame . It is the side draft that will be created from the AVT drive .. and the up torque from the exhaust side that I have concerns about . Thank-you Gerald m

gerald m

Yea I hear you blue t11 the exhaust side has very little to attach extra mounts too so I'm thinking that I will build a couple of beefy clamps and clamp the engine down to the frame solid at least on the outer two irons and then a couple of well placed braces from engine to frame . Thank-you for your time. Gerald m.