Topic: GTA/Ontario Engine Inspection & Rebuild Service

[kixbox]

Hi, after a long search, I finally found the right 1978 CB750.  The bike is in great shape all things considered and I am about to start my restoration & personalization journey, which I'm excited about. 

I understand the engine mechanics part and the inner workings, but lack any real-world experience in inspecting and rebuilding (plus I have NO tools and don't know where to begin to source parts).  My immediate question: does any one know of a place or someone in GTA/Ontario where I can have the engine inspected and rebuilt if needed?

My other question is about seeking advice: the engine turns over, but doesn't idle for too long and dies due to leak in one of the carbs (I will rebuild).  That said, in the spirit of safety plus me wanting to enjoy the bike and for it to last for a long time, do you think it would be worth paying someone to inspect it and open it up for a rebuild if required? Or should I take my time and do it myself (which I don't mind at all, but a bit overwhelmed).  I am not in a rush to ride it, and happy to put in the time even if in months/years. 

Any advice would be greatly appreciated.

Thanks in advance.

[calj737]

First, download a manual from this site. Locate the 3,000 Mile Service checklist and perform these tasks, 1 by 1, at your pace. This will assist you in familiarizing yourself with the bike, its components, and the proper condition for things.

As for rebuilding the carbs, do NOT replace the stock brass with cheap aftermarket kits. Use only Keihin brand components if absolutely necessary. The stock pieces should clean up perfectly well.

All the screws on your bike are JIS, not Phillips. So purchase a set of Vessel brand JIS screwdrivers, and Impacta (hammer operated impact driver) to remove any stubborn screws. If you discover stripped screw heads, its because someone before you used a Phillips.

Its difficult to locate knowledgeable shops to deal with these engines. If they've been looked after, and the mileage isn't extreme, likely it doesn't require anything but a complete and proper tune up. So don't be hasty to spend money before you spend some time. I'm sure the excitement is overwhelming, but there are far more horror stories than pleasant ones from new owners dropping bikes off at shops and spending way too much money, waiting forever, and getting back ore problems than they started with.

Start a Build Thread in the Projects section, you'll get heaps of helpful advice on where to go next.

[kixbox]

Thank you SO much calj737 for the prompt response, extremely helpful.

Your advice is sounds and one that I am going to go by as I make the initial first step.  I am planning to organize my thoughts and process this weekend and will initiate a project thread in the appropriate section.  As a first step, I got me a mechanic stool

[calj737]

First mistake. Primary tool for everyone is a can opener to keep the mechanical lubricant flowing freely 

[HondaMan]

If the bike has been sitting for quite a while, consider trying to ride it a bunch before you do much else. These engines have a way of self-healing in their valves when ridden, and also of rusting on their seat faces when parked. I have seen many of them go from less than 90 PSI of compression when 'reawakened' to over 120 PSI after 1000 miles of steady riding, once tuned up properly. Don't be surprised if it bobbles and stumbles a while before this straightens out: they were made to RIDE, not to hide in the garage.

[kixbox]

First mistake. Primary tool for everyone is a can opener to keep the mechanical lubricant flowing freely 

Yep


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[kixbox]

Thanks Homdaman.  I agree.

The bike sat with the previous owner for about 9 years stored and not running.  Getting to run to enjoy for a bit before the project is going my be my top priority approach.  I will provide an update on this thread on how it goes.  PS: bought your book, excited to get it next week.


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[kixbox]

Thank you both for the advice you have provided. 

A quick update: I got the engine to run for a while and took it out for a spin (about 25 kms).  I just wanted to get a feel for the engine and how the bike rides, it felt great!! I am no mechanic nor do I claim I have the knowledge on how to bring something like this to life - never even owned a wrench .  That said, I am learning a ton, really taking my time to study manuals, texts, videos, etc. 

This is a quick update out of respect given your responses (and to get a gut check on the direction I am going in):
1)   Basic step: I built a platform with front wheel chock (all made of wood, 8’ x 3’ about a foot off the ground) – super happy about this as it allows me to keep the garage clear for kids safety and it also allows me to put the bike away during the cold winter. 

2)   Got the engine to run: I am not sure how its suppose to sounds, but its sounds rough.  In order to keep the bike running, I had to adjust the idle screw to above 1500-2000 to keep it on (at times it needed to be closer to 2500 to stay running).  If it drops close to 1k, it slows down and dies.  I run the bike every day on the bench (center stand) for 10-15 mins and I adjust the idle screw to get as close to 1k as possible (getting there).  That said, it takes forever to start.  The good news: no smoke and no leaks (well, one minor leak from a screw near the clutch area).  All in all, I am happy to know the bike has solid bones and its glory days are not over yet.  QUESTION: re: the RPM and idling, is this a bad sign or simply tuning?

3)   I started the 3000 Miles Factory Maintenance list:
a.   Changed oil, oil filter
b.   Checked spark plugs (all seem to look identical)  some darkness on them evenly across all four, the but the side electrode all fairly white.   I am going to replace them anyway for extra measure, they aren’t that expensive. 
c.   Adjusted points gaps (were not set correctly) and timing is def off (I hear little farting during idle and when riding, nothing major, but I think the timing adjustment will take care of that). 
d.   Front brake was seized: took it all apart and cleaned caliper (internals were in good shape)

4)   @calj737: the bike already comes with Keihin brand carbs, which made me feel good. 

Side comment: the previous owner is super awesome, we keep in touch and help answers any history related questions I have - I feel lucky.  He also sent me a list of all the things he did to the bike over the last 10 years or so. 

This is how far I got and will continue the awesome journey.  I suspect the next few months will be about going through the maintenance list and riding the bike for a bit before I do anything else. 

I have a vision mainly semi resto-custom to my own taste (I started the design process for the look and color theme I want this bike to when all said and done).  Secondly and equally as important, it is about me enjoying new life experiences that I always had hopes of doing (rebuild a bike and rebuild a muscle car).  The muscle car has to wait for a bit given the stage in life I am in .

If you have any thoughts, please let me now. 

Once I go through the maintenance checklist, I intent to start a Build Thread in the projects section.