Author Topic: pull a CB 750 transmission  (Read 1253 times)

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Offline CB750 SS

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pull a CB 750 transmission
« on: January 23, 2008, 07:22:26 AM »
The project continues...

I've got the engine completely apart and I've got 3 questions.  I'm looking to replace the main chains and paint the bottom engine case.

How do I remove the transmission?  everything else just lifts out.  Do I need to remove the gear selection mech?

Is there a product I can buy the "eats" carbon build up? that's also safe on the engines. 

Can I run the cases throught the dish washer?  in prep for a light sanding then paint?

Do I need to replace the main chain tensioner spring?  Engine has 44K on it.

Sorry 4 questions.

Thanks, Denton

Offline 750essess

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Re: pull a CB 750 transmission
« Reply #1 on: January 23, 2008, 08:41:43 AM »
You should download the manual in the FAQ section. Yes, you have to remove the shifter mech, the instructions in the manual will be better than what i can give you.
Orleans Cycle Repair and Restoration
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Offline ken736cc

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Re: pull a CB 750 transmission
« Reply #2 on: January 23, 2008, 09:11:04 AM »
Consider replacing the following items: primary chains, primary chain tensioner, cam chain and all cam chain sliders and rollers. To remove the transmission shaft from the lower case, the oil guide/bearing holder, held in by 3 screws, must be removed. The transmission shaft then comes out the side.
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Offline scondon

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Re: pull a CB 750 transmission
« Reply #3 on: January 23, 2008, 09:44:18 AM »
I left my transmission, and kickstarter gear, in place when I ran it through the parts washer(giant dishwasher, basically). Important to apply WD-40 to gears and fork selectors afterwards to prevent rust, but otherwise OK.

You might want to pull the transmission to check for wear on the fork selectors and dogs. If so, it can be helpful to take a pic of the assembly before removal and keep gears/forks in order removed.

Consider replacing the following items: primary chains, primary chain tensioner, cam chain and all cam chain sliders and rollers. To remove the transmission shaft from the lower case, the oil guide/bearing holder, held in by 3 screws, must be removed. The transmission shaft then comes out the side.

x2 on all parts that need replacing. Definitely replace the primary tensioner if adding new primary chains. Check/plastiguage cam and rod bearings while you're in there.
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Offline paulages

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Re: pull a CB 750 transmission
« Reply #4 on: January 23, 2008, 10:07:31 AM »
a dishwasher works great for loosening crud and generally cleaning, but in my experience, the lower case needs a little help first. i use a parts washing cabinet first to get the heavy grease loose.
paul
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Offline mcpuffett

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Re: pull a CB 750 transmission
« Reply #5 on: January 23, 2008, 10:51:48 AM »
if you dont have a parts washer like me  ::) then some turpentine and a paint brush and a small compresser will help to clean parts, you will have to remove your neutral switch to get your selector drum out  ;), cheers Mick.
Honda CB750 KO 1970,   Honda VTX 1300 2006, Lancaster England.