Re: What to look for when buying a CB750

Posted by sgtslag on Aug 10, 2011; 1:55pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/What-to-look-for-when-buying-a-CB750-tp3227766p3242627.html

The K model sounds like he might have been tweaking the carbs, possibly he put pod air filters on it -- it would be quite a bit of work to put it back to factory.  My '79 runs just fine on 10% Ethanol, so it sounds like you might have to do the carb work to save on the additives.

The blow-by box is a plastic tank, beneath the battery.  The FSM shows it clearly, and draining it means removing a plug from a hose, waiting for the crap to flow out (30 seconds?) into a catch container, then replacing the cap.

For tires, I am sold on the Pirelli Route MT66.  Search the Internet for reviews.  They are the tire that I put on, front and back, on all three of my bikes (one sold earlier this year, the Honda is in the shop having blown a tube on the rear tire, last Sunday -- not a failed tire).

The Iridium plugs are NGK:  lower resistance to spark, fire nearly perfectly, every single time; runs smoother; starts very easy with the weaker coils Honda used in these bikes; will last 50k+ miles, which is good since they cost around $8-$9 per plug.

Progressive brand suspension:  made my '79 ride like it was a 2009!  Replace both the front fork springs, and the rear shocks at the same time.  The progressively wound springs means you get two different springs, in one:  one heavier duty, one lighter duty, each functioning simultaneously, giving a very smooth ride, for not a lot of money, all things considered.  Only buy the heavy duty springs on the rear shocks, if you will be riding two-up most of the time -- otherwise they are really stiff, and nowhere near as good at tracking the road surface, nor as comfortable or smooth...

A K&N Air Filter is nice, but spendy:  oiled cotton; clean once every 50,000 miles, good for 1 million miles; passes more air than a conventional filter -- no need to re-jet, or re-tune.

SpeedBleeders will make bleeding your brakes/clutch super easy:  just open 1/4 turn, attach drain hose; drain old fluid from reservoir, fill with fresh; start pumping the brake/clutch lever until reservoir is empty, refill with fresh fluid; repeat pumping/filling, until clear, fresh fluid, passes out the drain tube, then close the SpeedBleeder, cap the reservoir, and done until next time.

Seafoam:  add to the gas tank to dissolve varnish deposits in the fuel system -- 1 oz. per gallon of gasoline.  Add 1 oz. per quart of oil, to the crankcase, run the bike for five minutes on the center stand, shifting through the gears in idle, with the rear tire in the air; shut down (back in neutral gear), drain the oil, change the filter.  This will likely turn the oil black, as it dissolves the varnish, and sludge deposits, within the engine, and the transmission.  With regular oil changes, this won't need to be repeated for 20k to 30k+ miles.  Top off your gas tank, add 1 oz. per gallon of gasoline, prior to Winter storage, run it for a few minutes to circulate it throughout the fuel system, then shut it off for the season:  stabilizes the gasoline, dissolves any deposits over the Winter storage, helps it run great come Spring.

Battery Tender Jr. trickle charger:  smart trickle charger, maintains the battery without boiling off the electrolyte over the Winter months -- top off the battery's cells, plug it in, and forget it until Spring; install the plug connector to your battery, and plug it in after every ride:  tops off the battery's charge to full, helps prevent sulphation, which shorts the internal battery plates, destroying your lead-acid battery.

Optional safety/conspicuity devices to help motorists see you better:

http://www.amperite.com/assets/Documents/HEAD-ALERT-2%20Series%20Tech.pdf

HEAD-ALERT-2 Headlight modulator, with photo-switch (auto-magically turns it to on solid, when it gets dark out); legal in all 50 States, federal law, overrides all State laws; must be ordered directly from Amperite, at around $60 delivered.  No scientific evidence, but in my personal experience, riding three different bikes, all equipped with this, and the Brake flasher (STOP-ALERT), below, I've had fewer close calls with drivers not seeing me, not pulling out in front of me, as often.  YMMV.

http://www.amperite.com/assets/Documents/Stop-Alert%202%20&%202M.pdf

STOP-ALERT Brakelight flasher (motorcycle model):  flashes five times, in five seconds, then on steady, until you release the brake.  Really makes a difference in people noticing you in front of them, helps avoid rear end hits, tends to reduce tail-gaiting.  Can be ordered either from Amperite directly (order together with the HEAD-ALERT-2, to save on S/H), or you can get it from JC Whitney.