Topic: cam lift??

[Zig]

Hay all.
Merry HoHo.
Manual tells me lift should be .3150 intake/.2953 exhaust. This cam i have measures .298 intake/.282 exhaust, what am i missing here?? Engine serial# is 248xxx. Any words of wisdom would be appreciated.
Zig.

[fuzzybutt]

is it cam lift or valve lift the manual specifies? the geometry of the rocker arms increases the lift at the valves from the cam lift.

[Zig]

is it cam lift or valve lift the manual specifies? the geometry of the rocker arms increases the lift at the valves from the cam lift.

honda manual specifies cam lift. it may be a cam from a different year but i dont have the spec sheets to tell.

[Big Jay]

Did you measure the actual lift at the cam lobe, or at the valve spring retainer?

[Zig]

Did you measure the actual lift at the cam lobe, or at the valve spring retainer?

cam is removed and on bench. measured at cam lobe, using base circle as 0. in v blocks with dial indicator.

[754]

That would be cam lift, NOT valve lift.

When you give a serial #,  also mention engine type.

Which manual lists the lift?

[Zig]

That would be cam lift, NOT valve lift.

When you give a serial #,  also mention engine type.

Which manual lists the lift?

yes is cam lift i am asking about. is 1975 cb 750, the same cam we chatted about 2 weeks ago. specs are from honda shop manual, maybe k4 not clear on download.
just opened up a spare engine and removed cam, cam lift is .380 intake/ .358exhaust. has "andrews" and a "D"  stamped on end of cam, a regrind??

[754]

use the ANDREWS, probably not a regrind, you got lucky..

[Zig]

use the ANDREWS, probably not a regrind, you got lucky..

gonna look a little deeper see what else might be in there. stiffer springs would be nice.

[754]

Nice surprise eh??

did you have any idea?
..get a cylinder light, pull a plug, pretty easy to tell if its big bore.

[Zig]

Nice surprise eh??

did you have any idea?
..get a cylinder light, pull a plug, pretty easy to tell if its big bore.

because pistons tops will be a different profile??

[754]

Hi compression pistons are domed not flat & valve cutouts are more noticeable.

[ekpent]

I put an Andrews cam in a 836 I did years ago,still running good. Bought the motor for $50.00 at a swap meet,came from a wrecked bike and seller did not know it was even hopped up.. Paperwork for cam said to set valves at 4 thousands gap- little more that 3 and 2 for stock if you use it. Hope you find another surprise in there.

[Zig]

Nice surprise eh??

did you have any idea?
..get a cylinder light, pull a plug, pretty easy to tell if its big bore.

pulled the head, other than cam it looks stock, but is spotless clean no carbon, hatch marks still visible on cyl walls. i may have picked the wrong engine to rebuild. didnt start on this one because was seized but on closer inspection is only a little water got into one cyl. am gonna pour in some hot atf and pull the barrells.
ta.

[Zig]

Nice surprise eh??

did you have any idea?
..get a cylinder light, pull a plug, pretty easy to tell if its big bore.

pulled the head, other than cam it looks stock, but is spotless clean no carbon, hatch marks still visible on cyl walls. i may have picked the wrong engine to rebuild. didnt start on this one because was seized but on closer inspection is only a little water got into one cyl. am gonna pour in some hot atf and pull the barrells.
ta.

i looked again, with a vernier. is an 836cc

[754]

YEE..HAH!!!

dont the pistons look..umm..NOT flat ??

[Zig]

YEE..HAH!!!

dont the pistons look..umm..NOT flat ??

engine is in a dark corner,piston tops are black,not as pronounced a dome as i expected,my eyes are getting old...........ok ok, you were right!! there i said it.
now am gonna need gaskets to fit?

[754]

If they were flat, I would next have asked you to look at the top of yout clutch cover!

to see if it had been tapped for a turbo return oil line (1080 has a bike with that)

You need an 836 head gasket, you have a fun motor sitting there , how did you get it?

[Zig]

If they were flat, I would next have asked you to look at the top of yout clutch cover!

to see if it had been tapped for a turbo return oil line (1080 has a bike with that)

You need an 836 head gasket, you have a fun motor sitting there , how did you get it?

 needed a new project ( t160 is complete) so purchased a runner k5 from a fella in thunder bay, came with a spare /complete rolling chassis, a spare frame and engine, and a spare engine, 4 sets of carbs, a set of 4x1 headers and 2 big boxes of nos parts, mostly cosmetic. he mentioned one of the engines was freshly rebuilt but didnt mention ( or know?) to what extent. he had purchased it from a fella years ago for a project for himself and son but they never got to it.
 the engine has been run but not much and i wonder why. hopefully no internal damage.
 assume base gasket is stock 750?
 cheers. zig.

[754]

Uses stock basegasket with that. I would probably pull the barrels carefully and check if there is any slop in the rods, then put pack together. ..unless head came off easy & you think base gasket did not move.. a bit of a crap-shoot.. your call...