A few new rider questions...

[spmcleod]

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Just picked up a 1979 Honda CB400Ti a couple weeks ago, slowly doing the necessary things to get it running as best it can. Already did some repainting of the side panels and cleaned up the engine and drive chain...

Couple questions:

Would using anything above 87 be detrimental to the engine, as (i believe) it wasn't around when the engine was made?

My bike has a GVWR of 703, and a weight weight of about 400lbs... I'm 270, is taking my girlfriend on a ride around town a really bad idea? (130lbs)

I have a chrome megaphone style muffler that I bought for a scooter I used to have but never put on... it looks more like the original muffler than the one currently on... think I could put it on with no issues?

 

[cruiserider]

Congrats on new (to you) bike! Great starting point for cafe racer project!
- don't waste you money, 87 is good enough
- take your girlfriend for a ride, when you upgrade - she will get this bike ;-)
- if you put an open muffler, you will need to rejet the carb, plus figure out a way to mount that new muffler on your bike. Is it really worth it? If original one is rusted - get it powder coated...

 

[spmcleod]

thanks cruise... as far as the muffler goes it's not an open shot muffler, it does have a baffle and fibreglass packing, and to be honest I don't know they properly adjusted when they put this 2 to 1 on with this tip... it does pop a little bit on deceleration sometimes which makes me think it's running a little lean...

 

[croco]

Definitely stick with 87 octane. Increasing the octane only decreases the chances of engine knock caused by the A/F mixture igniting before the spark in high compression engines. I am certain your bike was not designed to run on 91 octane, so using it will not make it run smoother, will not give you more power, and you'd just be wasting money.

If anything, it will make your bike more difficult to start as I found out on my old RZ350. Only once I put 91 octane in my old RZ350, and while it ran well, starting it up was a pain. I don't know if your bike has an electric starter, but kick-starting a stubborn bike is NOT fun.

 

[BradW]

Congrats on the bike... I've had my '78 CB400 for about 12 years now. I replaced the mufflers shortly after I got it with aftermarket, but very similar to stock ones. I don't know about the '79, but the '78 came with dual exhaust.

I only run Shell or Petro Canada 91 octane in it only because it doesn't have ethanol. Any time I used 87 it ran really sluggish. I've had a couple mechanics tell me that older bikes and outboard motors don't run very will with ethanol added fuel.

Overall the bike is pretty bullet-proof, but there are tones of parts out there if need be. Keep up on your oil changes and regular maintenance and it will go forever!

 

[spmcleod]

That's what I've heard... that with regular maintenance they can last a long time. 79 did come with dual too in the day, but somewhere along the line mine got a two to one... so I don't know if they adjusted anything when they put that on either... I'm just gonna check out the plugs and get a sense of how it's running tomorrow for a few minutes and then bolt on the new exhaust and give that a ride around, and check the plugs after... worst case scenario I have to put the old one back on!

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