Topic: CB350 four with 1/4" valve clearance

[MoMo]

Yep, exhaust valves on both #1 and 4 had 1/4" tappet clearance when the bike came into my shop. No amount of adjusting would remove it and cranking the engne over did not change the clearance so I pushed down on the tappet with my thumb while cranking the motor with the electrice start and eventually the stuck valve loosened and I was able to adjust the tappets.  Removed and cleaned the carbs to free the stuck slides, cranked the motor quite a few times and eventually it roared back to life after 18 years of barn sitting.  Another sohc back to life...Larry

[fmctm1sw]

Sounds like someone may have adjusted them with the camshaft in the wrong position.  I've done it, mistaking TDC on the exhaust strolke with the compression...   

[MoMo]

Sounds like someone may have adjusted them with the camshaft in the wrong position.  I've done it, mistaking TDC on the exhaust strolke with the compression...   

They could not have been adjusted  with the cylinder at the wrong postition. Pretty sure the valve was stuck open, once it freed up it only took a minor tweaking to bring it into specks. Fortuneately for the owner.  I just took the bike up and down my street, runs decent but I never did like the 350 four all that much-too slow...Larry

[iron_worker]

Yep. Sounds like she was frozen in the guide.

I can't imagine that's good for the valve to be now sliding back and forth in all that corrosion....

Top end rebuild may be in that bike's future.

IW

[Sniper X]

I wouldn't call the 350F slow unless you compare it to something modern. Mine will stay with a 400f or even an average 500f. Mine might be abby normal.

[MoMo]

I wouldn't call the 350F slow unless you compare it to something modern. Mine will stay with a 400f or even an average 500f. Mine might be abby normal.

I was disappointed when it came out, my feeling is it should have been much faster than the 350 twin since it had two more cylinders. More of a gut feeling than confirmed stats.

Yep. Sounds like she was frozen in the guide.

I can't imagine that's good for the valve to be now sliding back and forth in all that corrosion....

Top end rebuild may be in that bike's future.

IW

I think my customer will ride it as is, could be OK as long as the oil is frequently changed...Larry

[cgswss]

To me, 350-4s feel very slow.  They have no torque and don't make any power until you get over 4K.  If your into tap dancing on the gear shift, they can be very fast for a "little" bike.  Sorta like my CB650 doesn't "feel" near as fast as my Norton 750, even though it has a lot more HP.  It's more fun to ride the Norton because I just twist the right hand  to pass, where I normally have to shift down twice to pass on the 650.

[MoMo]

To me, 350-4s feel very slow.  They have no torque and don't make any power until you get over 4K.  If your into tap dancing on the gear shift, they can be very fast for a "little" bike.  Sorta like my CB650 doesn't "feel" near as fast as my Norton 750, even though it has a lot more HP.  It's more fun to ride the Norton because I just twist the right hand  to pass, where I normally have to shift down twice to pass on the 650.

I feel the same way as you about the 650...Larry

[trueblue]

Size for size, twins should be faster than fours on the street, they have less moving parts, so therefore less internal friction.  They are generally lighter bikes and also their tourqe curve is generally more suited to street riding, more low down grunt.  As far as the 650 being underpowered, I have no issues with my 79 650Z overtaking.  If I have the missus on the back I click it down one cog just to give a little more acceleration, but by myself, I rarely have to.

[MoMo]

Size for size, twins should be faster than fours on the street, they have less moving parts, so therefore less internal friction.  They are generally lighter bikes and also their tourqe curve is generally more suited to street riding, more low down grunt.  As far as the 650 being underpowered, I have no issues with my 79 650Z overtaking.  If I have the missus on the back I click it down one cog just to give a little more acceleration, but by myself, I rarely have to.

It is smooth and powerful enough but there just seems to be something missing. I've been a Honda fan for 40 years but the 350f and 650 (and the77-78K )never did much for me-performance wise and aesthetics...Larry