Custom Honda CB750: Final Tweaks

Jarred's Custom Honda CB750 is all done but the carb tweaking...

Jarred’s Custom Honda CB750 is all done but the carb tweaking…

Jarred’s Custom Honda CB750 Super Sport is finally wrapped up, save for a few tweaks of the carbs.  Seems we have a bunch of custom motorcycle builds all approaching the finish line at the same time, all of them needing a little carb love…

Custom Honda CB750: Reaching the finish line…

Custom Honda CB750, with the much debated Firestone tires...

Custom Honda CB750, with the much debated Firestone tires…

It’s been an interesting build for Jarred, shaping this Custom Honda CB750 into the vision he had for it.  The bike had been sitting in a Brooklyn garage for years, and was rescued, stripped, and reassembled to his liking.  Along the way, Jarred cut and rewelded the tank, installed a custom oil tank, fabricated a custom seat and unique front brake mechanism (hidden under the tank).

The Custom Honda CB750 got header wrap to hide the condition of the stock pipes...

The Custom Honda CB750 got header wrap to hide the condition of the stock pipes…

There were more modifications, and some more fabricating, and eventually the Custom Honda CB750 began to look like a bike again, complete with alligator brake pedal (true Louisiana style!), oil pressure gauge, pod air filters and fresh powder coating for the frame and wheels.  The clean lines of the handlebars are enhanced by the removal of all controls, leaving a sleek look.

Some shop neighbors admire the "industrial" look of the Custom Honda CB750...

Some shop neighbors admire the “industrial” look of the Custom Honda CB750…

After rolling the Custom Honda CB750 outside to test the new jet settings in the carbs, some neighbors of the shop stopped by to have a look.  They have seen the progress during the build, and seemed pleased by the final result.  It’s always nice to see a smile on the faces of non-motorcycle riders, who simply appreciate the style and care put into this build…

7 thoughts on “Custom Honda CB750: Final Tweaks

    1. I think he like the tires. Not my bag, but not my bike either. Definitely needs some stability up front. I think that’s coming with the custom fender he was talking about.

  1. It is really hard to take anyone seriously who think those tires are a good idea.

    you keep mentioning a little carb tuning, but it is going to take more than a “little” to get those carbs dialed in with those pod filters – they just don’t like the airflow it creates. Honestly, he is better off taking the velocity stacks out of the airbox and running them unfiltered than he is trying to make that cheap shit work.

    1. Kerry, when you say “good idea,” you are referring to data you have on these tires directly leading to accidents? I know people have been criticizing them in the past couple years, but I’ve never research whether it was a style or actual functionality thing.

      The mentioned “carb tweaks” are relative. It’s never easy to get these things correct (if ever), but I like to leave a little hope at the end of article. That’s just me 🙂

  2. I don’t have “hard data” because hard data doesn’t really exist for it. I don’t think anybody has done a study relating those tires to accidents. I have however bought a set a long time ago and found them to be less than round (seriously they were deformed). I thought it was a freak occurence but I have had other friends who have purchased them and found them either difficult to balance up or just completely out of round. I have in two instances personally seen tread deformation (one was almost a seperation) when the tire was used in “spirited” riding. I have ridden bikes with those firestones and found their ride squirrely at times, but who knows if that is a product of the pavement and tread or a manufacturing defect, or someone just not balancing them properly.

    But forget all that – ever notice how hard it is to find a tire spec sheet on them? other brands will tell you the weight rating, the speed rating, right off the bat – not on those firestones. If you email coker about them they tell you replica/vintage tires don’t have load ratings or speed ratings <—- that is some pretty dodgy CYA shit from a company otherwise known for good products. They aren't DOT rated but who knows if that is just coker's way of getting around the expensive rating process or if there really is an issue they are covering their ass about. For years they were marked "for display purpose only" and I don't think much has changed in the manufacture of them.

    From what I am hearing on the street 3000 miles is all you get on a sub 500lb bike on one of those tires. word around the campfire is that they are only "safe" to 80-90 mph, and even that is unverifiable. Coker originally built them so owners of 40s and 50s' motorcycles could have an accurate looking tire at shows, I don't think they were ever intended to be used in the way they are being used right now.

    Honestly, most people who use those tires buy them for the look and aren't aware a spec sheet doesn't exist for them. The thing that disappoints me is that avon still makes the speedmaster, a real deal vintage tire, with the same tread since the 1950s that is load rated, speed rated (112 mph), and DOT approved. They also make a DOT approved tire called the safety mileage that looks like the firestone tread and is also speed and load rated. Both of these tires are cheaper than the firestones.

    cb750s are espically sensitive to how air gets in the carb. it is more work than other bikes to dial them in "properly" and even that is going to be sub par. I have only see people lose hp on a dyno with pod filters on a cb750 – never stays the same or makes HP. The question I always ask people when they talk about cb750s and pod filters is: "do you think you are smarter than a 1960's honda engineer?". There is a specific science to velocity stacks and how they tune airflow. The carb rubbers in a cb750 are velocity stacks shaped precisely to feed the cb750 engine – removing them means the carbs are just sucking in roiled air and often in an inconsistent volume. How well do those stacks work? HRC and RSC ran endurance racers with just those actual carb insulators or v-stacks with the same shape with much success. Never trust anyone who tells you getting rid of the stock airbox on a cb750 "derestricts" it. It doesn't. The cb750 engine has valves and ports in the head that are too small – there is the restriction. The cb750 airbox is an excellent example of the science behind plenum air chambers something that all modern cars and bikes take advantage of today.

    1. These options for the Firestone are good to know. Still can’t imagine going for that look myself – but never say never.

      The pod issues are well documented, and your point about the engineers over at Honda designing it purposely is well heeded. But as we know, these changes are often driven by something other than engineering.

      I put a set of pods on my CB550 to keep shit out of the back of the carbs while waiting for new boots to arrive in the mail. I happened to fire it up at one point with those on there – and It ran like a nightmare. The pods were immediately removed and replaced with balled up shop towels (clean of course). It may have run better with the towels, as far as I could tell. Fortunately I didn’t need to start it before the stock air box was returned to its rightful place.

      Not sure if the CB750 is even more temperamental – but if so, I’d want even less to do with it. But as stated, not my build, not my time.

      Jarred is pretty crafty though – and I’m sure he will either get it right or swap it to make it so.

  3. Pingback: Custom Honda Cb750 Super Sport Jpg Moto Honda Cb 750 F Super Sport : OtoSPEED

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