Honda CB750 Sandcast

Starting Work on CB750-1001250

Wayne

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Wayne..... thanks. I gather “early bikes” didn’t have the US pints indicated. Will be interesting to hear what defines and “early bike”? I will check my oil canister bolt.

http://cb750sandcastonly.com/smf_forum/index.php/topic,2211.msg15948.html#msg15948
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BenelliSEI

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Interesting details! Thanks Wayne. Where can I purchase the “early” oil decal (6.0pints)? My existing oil filter bolt takes a 17mm wrench and definitely looks “aftermarket”. Sources for a 14mm headed bolt?

Today I finished re plating some engine mounting hardware and building up a clean set of passenger foot pegs. I still need to decide how I am restoring my seat, but the roller is done. Engine top end work is next.
John D.


BenelliSEI

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Heading out to our first 8 Hour Endurance Race at Mosport (Canadian Tire Motorsport Park) this weekend, so this project is on hold for a while......,
John D.


BenelliSEI

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So it’s been  awhile! The race season was a hoot. The LEXUS was new to our Team. It was built for the American Grand Am  Series by a group of Lexus factory engineers. It had not been raced in several years, so took us a while to sort. The tired race motor finally let go mid season and we swapped over the “tuned” head to a very low mileage, stock  motor. After that it ran like a train. It’s a big six, and has lots of HP and even more torque. We added a 20 gallon fuel cell so each of us could stay in the car for a full 2 hours (the races are 8 hour enduros). Power steering and brakes make it easier for long sessions, and the brute is fun to drive. Not as fast as some of the Porsches and newer imports, but very satisfying....

Took the Benelli 750 SIE to the Cobble Beach Concours, late Fall. No prizes, but a fellow from Florida took a real shine to it, so it’s headed there now. Also, sold the 1970 cb750K0 to a local guy who put +1000 miles on it. Completely stalled out on the Sandcast and Rickman CR projects, but getting back to it now.
« Last Edit: November 30, 2022, 06:15:21 pm by BenelliSEI »
John D.


BenelliSEI

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Back to work on #582. I had this engine running nicely in the frame, before tearing down the bike. Great oil pressure, no chain noises, all good. Pulled the head and then got stumped..... the bore portion was solidly stuck to the cases. An I mean STUCK. Built a lifting frame and hung it from the rafters. Despite a ton of soaking, penetrating muck, etc., it would not come apart.
« Last Edit: December 02, 2022, 06:28:37 pm by BenelliSEI »
John D.


BenelliSEI

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Today I added a pair of threaded rods sticking up from the angle iron bolted to the barrels. Built a bridging platform across the top of the head studs and pulled up with the threaded rods. Despite a tremendous amount of preload nothing budged UNTIL I super heated the base of each front stud where the dowel tubes are located. Several huge , scary hits with a brass drift and a 2.5 lbs. hammer and it finally “popped”. So pleased, I forgot to take a photo. Will take a few next shop day.
John D.


BenelliSEI

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Here’s a photo of the “lifting rig”.
John D.


BenelliSEI

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Moving forward again. Stripped the head today. “Homemade” valve spring compressor works well!
« Last Edit: December 02, 2022, 06:31:24 pm by BenelliSEI »
John D.


BenelliSEI

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Chatted with Brian at Rocket Performance today. They are close to me, in Whitby, Ontario. The two major components pictured above will get my first test with “vapour blasting”. I’ve seen other stuff he has done, it looks like new when completed, with no alterations to base material.
John D.


BenelliSEI

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Repairing a few bent fins will be the next order of business when the parts return from vapour blasting. The top end will get a light hone, rings and all new gaskets and seals.
John D.


BenelliSEI

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Very successful repairs completed!
John D.


BenelliSEI

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Pistons in, light hone, new rings. All well within specs. The oil rings in my RK set were too tight in the grove. The originals were not 1/2 way to the wear limit. Back in.

Guess who managed to fire a piston pin clip into the crankcase, years ago?
John D.


BenelliSEI

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Started assembly today. Side covers and paint when the weather warms up......
John D.


BenelliSEI

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A few wet days led to some shop time. Determined to do more riding than work, this summer. Buttoned up the top end. After this photo, rockers went in, valve clearances set.
John D.


BenelliSEI

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It’s been a while! A few projects got in the way and I’m still busy endurance racing an ex Grand Am LEXUS IS300 a Team of friends. Last week I received an invitation to the Cobble Beach Concours. A few years ago, I won best in show with my 1970 cb750. Took my Benelli SEI there most recently and this September I want to take the Sandcast. I typically don’t attend shows, but this is a spectacular event. Back on it, with a deadline!
« Last Edit: April 07, 2024, 04:29:41 pm by BenelliSEI »
John D.