[Reima Saarinen]

Hi friends,

Some help or advice is needed.

Even my CB450K5 looks great it anyhow has some problems.

The 2nd gear seems like slipping while accelerating in about 4000 r/min, there is no noice anyhow.
Is there something very wrong or wearness in the strollers and means this a big repair?

Also there is problems with the carbs and idle running goes up when the engine is warm and spark plugs seem to blow up, the breaker contacts have to been changed.

 

[Lefty]

Could be clutch slip or worn detent? The carb problem sounds like an air leak. Dried up felt throttle shaft seals and cracked old rubber boots are common causes.

 

[ancientdad]

If a gear in a Honda constant-mesh transmission is "slipping", it would be trying to jump out of gear - the engagement "dogs" would be only partially engaged and it would "jump" out of gear, not feel like slipping (like a slipping clutch). It's possible, of course, but a lot less likely than clutch slippage

 

[Reima Saarinen]

Thanks guys!
We will study these.

Reima

 

[Reima Saarinen]

Found these in MCSNL, a wild quess what parts should be changed and fixed concering the 2nd gear?

Reima

 

[frogman79]

On your parts fiche above, check to make sure that the clip (part 12) and washer (part 2) holding the shift shaft are in the correct place. If they have fallen out of the grove replace the clip with a new one and see if that helps.


2nd gear issues with 450s are usually the roller wheels and the star gear on the side of the shift drum. The large roller (part 11) wears the pin out faster than the wheel so the wheel will sit further back from drum and will not apply enough pressure to hold the bike in 2nd.

The star on the end of the drum (part 8) wears out which causes groves in the star points that can make the shifting feel soft and when power is applied the gears may just jump out because nothing is holding them in.

2nd gear shift forks are ones that may get bent as well since we use 2nd a lot around in town driving.

having issues with the picture size here is the link to the page I got it from. Western Honda Powersports- Honda Dealers 50 years In AZ Motorcycles ATVs Sales Parts Service & Repair

 

[Reima Saarinen]

Hi mates,
the reason for 2nd gear's problem is now clear, two engine "doctors" examined the gearbox. The fork of 2nd gear was worn out.
Some work for wintertime and something else will be done in the same time.
Hoping that in the Spring CB450K5 runs like a new bike.