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Pointers for engine rebuild?

Posted: Fri Aug 12, 2011 10:48 pm
by bobber01
Have a rattle in the CBX which cann't get rid off. Fairly confident its the primary chain so have to take the beast apart. Top end was done less than 3000kms ago so don't really want to open that up. Seen in 'The CBX Book' , on page 50/51, Honda assembling the engine halves with the top end all in place. Anyone do this method before? And any pointers would be appreciated. Going to source some parts soon so have them ready when I open up. Any special tools needed? I had a clutch nut tool but cann't find it. I know I'll need a clutch nut and a primary chain.

Re: Pointers for engine rebuild?

Posted: Sat Aug 13, 2011 8:01 am
by cbx6ss
What year engine? When do you hear the noise (always, idle, accel, decel, certain rpm)? Answers could be a factor in the cause.
/r
Brad

Re: Pointers for engine rebuild?

Posted: Sat Aug 13, 2011 9:50 am
by bobber01
cbx6ss wrote:What year engine? When do you hear the noise (always, idle, accel, decel, certain rpm)? Answers could be a factor in the cause.
/r
Brad
Bike is a 1980 with a clutch basket from an '82. Carbs been sync'ed. Rattle is between idle and about 1800rpm. Part of my rationale for suspecting the primary is that the pulsar ignition plate will not properly align when doing the static method. Plate adjustment slots would need about to be about 1/2 a bolt thickness longer.

Re: Pointers for engine rebuild?

Posted: Sat Aug 13, 2011 1:57 pm
by cbx6ss
Sounds like you are past most of the usual suspects.

Re: Pointers for engine rebuild?

Posted: Sat Aug 13, 2011 9:49 pm
by preston
You can pull the crank without pulling the top end off, although you will have to pull the cams. Might be a good tome to change all the drive chains. Pay attention to o-ring s and sealing compnents for the oiling system.
Also, now's the time to adjust your oil pump releif valve springs to get max pressure from your pump. I do offer an exchange progeam or adjust yours ofr you.

Re: Pointers for engine rebuild?

Posted: Tue Aug 23, 2011 6:24 pm
by bobber01
Been having an issue with an engine rattle I have when at idle coming from the lower section. I also noticed I cann't properly align the pulsar generator to the crank marks, which leads me to believe the primary chain is stretched. The crank can turn before the pulsar moves .This afternoon I checked the amount of primary chain play in an older CBX lower half I have. That engine has the primary turn with the crank, regardless if going forward or reverse, with no delay whatsoever. So this fall I'm hoping to take the engine apart with a goal of having it done for at least one ride next year before giving it to my son.
Having some health issues so any pointers such as special tools, shortcuts, part sources I would greatly appreciate. I did strip one down years ago but don't remember what I needed and tools, parts then readily accessible.

Re: Pointers for engine rebuild?

Posted: Wed Aug 24, 2011 8:18 pm
by Jeff Bennetts
Have tried to adjust the cam chain tensioners, fornt and rear?

Re: Pointers for engine rebuild?

Posted: Thu Aug 25, 2011 8:37 am
by bobber01
Jeff Bennetts wrote:Have tried to adjust the cam chain tensioners, fornt and rear?
I've adjusted the 'A' and 'B' chains and physicially checked the tensioners for movement. Based on not being able to line the pulsar ignition properly to the crank I'm thinking its either a stretched primary chain or damaged/worn primary adjuster as it would be the only non-geared connection between the two.
Checked some of my CBX stuff I have and did find a clutch nut tool. Manual says a 55mm pin spanner is required for primary shaft nut removal so hoping one off the multitude of shock adjusting wrenches I have will work. Thinking I may be able to put the engine on a bench, upside down, to remove the lower case without disassembling the top end, other than cam chains, and work on it that way.
Jeff, were you the member I sold a Dyno-Jet Stage 3 kit with individual pods too a few years ago? How did they work for you?

Re: Pointers for engine rebuild?

Posted: Thu Aug 25, 2011 4:05 pm
by Jeff Bennetts
They went on a friends bike who removed some Smoothbore flatslides and went to stock carbs before selling his bike.

Re: Pointers for engine rebuild?

Posted: Thu Sep 01, 2011 8:47 pm
by bobber01
4755

Took the 'spare' engine apart yesterday, removing the primary chain and tensioner, looks good. Today I started taking components off the engine I want to check the primary on. In doing so I remembered a friend of a friend pasted on a quick way to check the primary chain/tensioner. An individual on the France CBX site suggests removing the spray tube from behind the alternator and check for marks. As this photo shows the chain has definetly been hitting it. The 'spare' engines tube had no such marks. In the photo album I've posted a picture with the two tubes side by side. I have to salvage what parts I can from the two engines as appears not many OEM parts around. Was hoping to have the engine apart to confirm either chain/tensioner/slides but the body wasn't up to the task. Hopefully this weekend.