1975 Honda CB750F: Reader Resto

Date 30.5.2013

Presented by
  • Motorcycle Trader

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FOUR FIXATION

After putting in two years’work to restore my 1975 Honda CB750F it was a bit of a surprise to find that it took several months more to sort out an engine gremlin. Getting on top of that issue taught me a couple of things. The first was that what seems like a fuel problem isn’t always a fuel problem. The other was that when someone tells you that you don’t need to check the timing again because they’ve already done it, checking the timing should then be the first thing you do. The trade-off, though, is that I now have a spare set of rebuilt carburettors mounted in a wooden frame to remind me of this folly. I also have a skill set I didn’t have when I started the project – I can rebuild CB750F carbs blindfolded.

It all started when one of my mates from the Ulysses Club, Chris, showed me his 1975 Yamaha XS650, a recent purchase that he was tidying up to use as a second bike. When I said that I wished I had the space to do something like that his response was, “Why not do it here, George? My garage is big enough.” That was all the encouragement I needed. Now all I needed was a bike.

IT’S A HONDA

Then I remembered my brother-in-law’s old Honda. He had given it to his son to ride but it had ended up in an accident and had spent the next several years living in the backyard partially covered by a small tarp. Another Ulysses friend, Gary, offered his van to bring home my pretty sad looking acquisition. When I told other club members that I thought a good clean up and some minor repairs would soon have my Honda on the road as my second bike, most nodded politely, while some wished me good luck and others reckoned it was too far gone. They were probably right but I couldn’t see that for the rose-coloured glasses I was wearing.

I took the bike home and spent four weeks in my spare time cleaning everything to get an idea of what was salvageable and what wasn’t. Then I tried to get the motor started; if it hadn’t started I’d probably have given up there. It did start and spewed out the traditional black smoke from years of standing still. With it running I took it for a test ride on the gravel lane next to my place to check it out generally. The gears changed okay until you went for third, which gave you another neutral. Fortunately fourth and fifth worked. The brakes sort of worked and most of the lights seemed to function.

LET’S DO IT

As soon as the strip-down started we discovered that the fork stanchions were bent. After not finding anyone who could straighten them, I was fortunate to find Andrew from Puds Four Parts. He put together a secondhand set using my old fork lowers and some uppers he had in his vast inventory of spares. He would turn out to be invaluable when it came to getting those parts that were essential to get things going that no one else had. He got me out of a jam many times.

With everything removed from the bike, there were a few things that I wanted to get sorted straight away before I started putting money into the mechanicals. I took the tank and sidecovers to MPR in Sunshine to talk about repairs and painting. The sidecovers were broken in several places and I wasn’t sure they could be fixed. I’m happy to say that I was wrong. I stayed with the Honda’s original ‘Sunrise Orange’ paint colour. Everything came back looking brand new; there was no sign inside or out of the plastic welding that had taken place.

Next came repairs to the seat base after I had searched unsuccessfully for a replacement F-model base. John, another Ulysses man, offered to remove the rust and then fibreglass the base. Dave (yet another club member) re-upholstered it. It’s not original but I like the look of it. When an original one did become available I opted to stay with mine. The bike was never meant to be an original restoration – it was meant to be a cheap way to get a second bike (although it didn’t quite turn out that way).

THE SERIOUS STUFF

We removed the engine and had the bores honed and measured. It was still within tolerance to take standard pistons and rings, so the original pistons were cleaned in sugar soap, polished and fitted with a new set of rings. The head was checked and the valves re-seated. The third gear in the gearbox needed to be replaced so this was done while everything was apart (all three dog teeth were broken off – we found them in the sump).

With all that sorted the engine was put back together with new gaskets and stainless hex bolts. Then we painted it and wrapped it in bubble wrap until it was needed.

The frame was rubbed back by hand. It’s a slow and tedious job I’d prefer never to repeat and we painted it black and then applied a layer of clear coat. Wheels were cleaned, checked, straightened, had new bearings added and were re-tyred.

I was glad I spent time numbering all the wiring connectors and making a list while pulling them apart, as it was invaluable in putting all the electrics back together. Surprisingly enough, very little fiddling was needed to get everything working. The starter button was the tough bit. With my nonexistent soldering skills another club member, Des, came over and fixed that up for me.

READY, SET – GO?

Once everything was back together another friend, Paul, came over and helped set the timing and tune the carburettors (he had also helped assemble the motor). It ran a bit rough but l rode it anyway, thinking perhaps that’s how these old bikes were. Eventually I took it to a workshop to have it checked out, but it came back pretty much the same, with the comment, “That’s as good as it gets with these old things.” After several more months of mediocre running, my friend Paul came back to have another look at it. After discovering that he had set the timing wrong to start with he put it right. Finally, from that moment it ran great – job done.

LOOKING BACK

With very little mechanical knowledge when I started, most of my work on the Honda was done following the instructions in workshop manuals. I’ve learned a lot along the way from those books and from helpful friends.

My project to tidy up an oldie to use as a second bike while picking up a few skills along the way was a success, but it cost a lot more than I expected. In fact it cost more than the 1987 GPz1000RX I was riding when I started on the Honda. I’ve since sold the GPz and replaced it with a 2003 ZZ-R1200, but I definitely won’t part with the Honda as I truly feel this is ‘my’ bike – it has a lot of me in it.

Thank you to all who helped with my little project. Special thanks to all my Westgate Wanderers Ulysses friends for the large role they’ve played in educating me and generally helping me with the resto.

Unfortunately my health hasn’t been too good lately. Lke a number of my fellow Ulysses members I’m fighting ‘the Big C’. This means that the bikes spend most of their days under covers. But I start them as often as I can and I still hope to get the chance to ride them with my mates again soon.

Shopping for small stuff

A lot of miscellaneous parts are needed to bring an old bike up to scratch.  When you’re starting out you tend to concentrate on the big-cost items. But it’s the cost of the growing list of smaller items that can surprise you when you
total it all up at the end.

Here are the items I needed to replace to bring the Honda up to the standard you see in the photos:

• Front guard
• Halogen headlight
• Tachometer
• Brake master cylinder
• Caliper seals and pistons
• Brake levers front and rear
• Chrome covers for the gauges
• Mirrors
• Gear lever
• Gear selector arm
• Neutral switch
• Chain and sprockets
• Decals
• Warning stickers
• Tank badges
• Grips
• Indicator lenses
• Airbox and breather seals
• Hoses and filter
• Carburettor rubber connectors