Author Topic: Honda CB900F  (Read 13772 times)

thumperdh

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Honda CB900F
« on: December 15, 2013, 07:07:53 pm »
I'm heading down to look at a 1982 CB900F this weekend, i know the bike has been sitting and is complete with a title but that's all I've got so far. Can anybody provide some insight to me as to what to look for with this model? I've heard the engine had valvetrain issues and second and third gear issues but that's about all I know.
1982 FT500
Conti Classic Attack tires
Foam filter mod
Round headlight
Rejetted carb
Progressive springs
Supertrapp muffler
Thumperstuff header

J6G1Z

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Re: Honda CB900F
« Reply #1 on: December 16, 2013, 09:46:53 am »
Well... I began writing up a reply & just about had it done when my computer choked & I lost it all. I don't know much about the Honda CB series. I started looking for a big bike that I could take two for a ride comfortably & started with the idea of a CB750. They were a solid & simple air cooled design, sold about a million or so & they used to be available cheap. All of a sudden everyone thought their CB750 was a collectors item, or a CAFE bike & worth big $$$'s. It was ridiculous some of the prices I saw for old rat bikes. I then started looking at Yamaha's & the FJ series. You can find a lot better deals on Yamaha's most of the time.

Here are a few interesting links that I found by doing a quick Yahoo search on 1982 CB900F. It's a good looking bike!

http://www.nadaguides.com/Motorcycles/1982/Honda/CB900F-SUPER-SPORT/Values
http://wheelsacademy.com/a1/hondaboldor/Test/The%201982%20Honda%20CB900F.htm
http://wheelsacademy.com/a1/hondaboldor/Test/The%201982%20Honda%20CB900F_test.htm
http://www.hemmings.com/hmn/stories/2013/07/01/hmn_feature4.html
http://en.wikipedia.org/wiki/Honda_CB900F
http://www.cyclechaos.com/wiki/Honda_CB900F
http://www.motorcycleclassics.com/classic-japanese-motorcycles/honda-cb900f.aspx#axzz2nevzIFhA
http://www.bikeexif.com/custom-honda-cb900f
http://www.ehow.com/list_7612174_1982-honda-cb-900f-specs.html

Good luck & let us know how you do. Those 4 cylinders are a whole ‘nother story when you grab some throttle.

J.
« Last Edit: December 16, 2013, 10:02:50 am by J6G1Z »

thumperdh

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Re: Honda CB900F
« Reply #2 on: December 16, 2013, 06:07:37 pm »
Good luck & let us know how you do. Those 4 cylinders are a whole ‘nother story when you grab some throttle.

Thanks Jon, from what I've seen the thing is a total basket case, but the price is so low that unless the frame is bent/rusted out I should be able to make my money back if it has a blown motor. I'll post some photos when I drag her back home and up the stair case into my apartment. Man is my room mate gonna be pissed when he comes home after Christmas and finds a nice oily dirty motorcycle where the couch should be.  8)
1982 FT500
Conti Classic Attack tires
Foam filter mod
Round headlight
Rejetted carb
Progressive springs
Supertrapp muffler
Thumperstuff header

J6G1Z

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Re: Honda CB900F
« Reply #3 on: December 17, 2013, 07:32:01 am »
Oh... I thought you were looking at a bike that you could ride. Do you plan to part it out, or try to rebuild it?

Be careful with those basket case bikes. Often there are several expensive parts missing from the basket.

Here is another link: http://wheelsacademy.com/a1/hondaboldor/Test/Teststart.htm

Good luck
J.
« Last Edit: December 17, 2013, 07:44:59 am by J6G1Z »

thumperdh

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Re: Honda CB900F
« Reply #4 on: December 17, 2013, 05:37:36 pm »
Oh... I thought you were looking at a bike that you could ride. Do you plan to part it out, or try to rebuild it?

Be careful with those basket case bikes. Often there are several expensive parts missing from the basket.

Here is another link: http://wheelsacademy.com/a1/hondaboldor/Test/Teststart.htm

Good luck
J.

I've ridden one before, i've also spent extensive time on an 1983 GS1100E. I'm not sure what the plan is as of right now, i've rented a trailer in hopes to bring it back home but if it looks too gone i'm gonna skip it. The price is so low that if I can determine that I can double my money on parting it out i'll take it. And if it seems to be an easy fix, i have another rider. Who knows. I'll post up my decision on the buy/pass part/fix on Saturday evening when I get back home.
1982 FT500
Conti Classic Attack tires
Foam filter mod
Round headlight
Rejetted carb
Progressive springs
Supertrapp muffler
Thumperstuff header

J6G1Z

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Re: Honda CB900F
« Reply #5 on: December 18, 2013, 06:48:36 am »
How far do you have to go?

I rented an open trailer from U-Haul that was designed to haul one bike in the center. Think it cost me $20 for 24hrs.

The CB900F sounds like a neat bike based upon those articles above. That custom white one in this link: http://www.bikeexif.com/custom-honda-cb900f  looks real nice! That guy did a hell of a good job on it.

Good luck on your new adventure & may the Bike Gods smile upon you.

J.

thumperdh

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Re: Honda CB900F
« Reply #6 on: December 18, 2013, 09:02:17 pm »
How far do you have to go?

I rented an open trailer from U-Haul that was designed to haul one bike in the center. Think it cost me $20 for 24hrs.

The CB900F sounds like a neat bike based upon those articles above. That custom white one in this link: http://www.bikeexif.com/custom-honda-cb900f  looks real nice! That guy did a hell of a good job on it.

Good luck on your new adventure & may the Bike Gods smile upon you.

J.

It's about 120mi away from me. I'm doing the same thing with the open top Uhaul trailer, what a life saver man, you can't beat that deal for $20 bucks.
1982 FT500
Conti Classic Attack tires
Foam filter mod
Round headlight
Rejetted carb
Progressive springs
Supertrapp muffler
Thumperstuff header

J6G1Z

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Re: Honda CB900F
« Reply #7 on: December 19, 2013, 07:17:25 am »
Make sure you have the right sized Tow Ball on the back of your tow rig, or they'll want you to buy a new one before they'll let you have the trailer. I had to buy a new Ball because the shank on mine was the wrong diameter to fill the hole on my drop hitch properly. Luckily their pricing on a new Ball was reasonable at the U-Haul place that I went to.

Good luck
J.

Bucko

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Re: Honda CB900F
« Reply #8 on: January 14, 2014, 04:35:52 pm »
Just stumbled on this post now (always late to the party).

I have both a 900F and an 1100F (had the 900 since new, 1100 more recently acquired).

Generally the F's are relatively reliable and can take some beating but there are a few known weakness and issues.

It's not the cams that are the problem (although they are generally thought to be made of soft steel so they can wear out however probably not really an issue if you’re not racing it- and as with most bikes, oil changes are critical); the problem is with the cam chains - they can snap which of course leads to all sorts of problems and expense.  To compound things, the newer superseded cam chains are not as strong as the originals.  Believe it or not, lots of folks leave the original cam chains in when doing a full rebuild.  The crappy new cam chain problem has been somewhat mitigated recently by the discovery that a Yamaha Raptor apparently uses the correct size, but much stronger cam chain.  In addition, there's a fella in Auz that makes replacement cam chain tensioners and guides that are supposed to be a vast improvement over originals (which are no longer available) and which basically eliminate the faulty chain problem; personally, I think the jury is still out on their effectiveness (just because it too early to sell for sure).  If you found a bike that wasn't beaten, and you don't beat it, you're probably fine.

Adjusting the valves is critical.  Most folks think the factory recommendation (two thou, I think) is way too tight and should be more like 5~6 thou.  Misadjusted valves will display all manner of strange starting and running behavior.  In addition if the valves are to tight, they can burn which is an expensive problem to rectify, even if you’re doing it yourself.


There's a problem with the clutch: the dampers in the clutch basket are made of rubber.  When they get old, they shrink a bit and become hard which causes the basket to knock around a bit.  Not really a problem, but you'll find the bike will probably make a strange rattle sound at idle with clutch out, pull in the clutch and the noise disappears.  They all do it.  There's a guy in Holland that sells a kit to replace the rubbers with new ones which eliminate the rattle.

Similar rubber dampers are in the primary shaft (or secondary shaft, or some shaft) and they too will shrink and become hard and make very embarrassing knocking sounds when cold.  Not a deal breaker unless you’re doing major surgery anyway - replacements used to be available from Honda but recently maybe not??  You'd need to split the crankcase to put them in.

Charging system can cause problems: the F’s have a true alternator with an excited field rotor.  All that high RPM spinning can cause the wires in the rotor to chaff, and lead to a short circuit, which if left long enough, will take out the R/R due to overheating trying to pump more current into the faulty rotor.  Easy fix, but could leave you stranded.  There are some easy common measurements to make to help ensure things are working as they should (but measurements not infallible due to high speed nature of spinning rotor).  Aftermarket and rewound rotors are available in addition to R/R’s.

Finally, the quality of the original valve seals in these very hot running engines was really crappy and most of these older bikes with original seals burn a lot of oil.  Fortunately, newer Viton seals completely eliminate the problem, and if you’re creative, you can change them without removing the head, but you will probably have to remove the motor from the frame (although some have even got around that).  Unless you’ve found a very low mileage model, and even then, you’ll probably want at some point to change the valve seals.

The one mechanical item that will prevent perpetual rebuilding of these bikes is the oil pumps.  No longer available from Honda and even good used ones are almost impossible to find.  Probably not an issue for you but maybe for some potential rebuilder down the road.

Lots of these bikes were sold so there's plenty of used parts out there - EBay is your friend.  Not much in the way of aftermarket parts with the exception of oil and air filters and generic parts like bars, tires, etc.

These bikes still provide a spirited and fun ride but are outmatched on every scale by newer bikes (some diehards would disagree with that point of view, of course) with the exception of looks - In case I didn’t mention it, I think these F bikes are among the prettiest naked bikes ever built (completely biased opinion).  :o

If your jurisdiction is like mine, and if the bike is in good shape, you may be eligible for 'collector’ insurance which makes riding these old bikes very economical.

That's about it: change the oil, adjust the valves, ride.

There's a very active forum with huge amounts of good advice, technical information and lots of involved enthusiasts: http://www.cb750f.com/

Hope this helps.

PS: Forgot one big thing: the starter clutches are finicky and prone to fail.  They give you a warning before they die (and you can always bump start) and since parts are available and the repair is relatively simple, it's no big deal really.  Recently some guy has adapted a Yamaha R6 (I think) starter clutch to fit which permanently eliminates the problem (although again, that solution is new so AFAIC, the jury is still out a bit).

« Last Edit: January 15, 2014, 09:59:22 am by Bucko »

thumperdh

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Re: Honda CB900F
« Reply #9 on: January 15, 2014, 01:41:48 pm »
Well, here she is.

http://imgur.com/a/nQb5p

And for the grand total of $220 i think i did alright. It doesn't run from sitting for a while but that's a pretty simple fix. I already took off the carbs and i'm in the process of sorting them out. Only issue is that i'm working outside, it's been raining on my only days off and now i'm sick in bed on the only day off i've had in over two months that it hasn't rained.
1982 FT500
Conti Classic Attack tires
Foam filter mod
Round headlight
Rejetted carb
Progressive springs
Supertrapp muffler
Thumperstuff header

J6G1Z

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Re: Honda CB900F
« Reply #10 on: January 15, 2014, 02:52:27 pm »
Not a bad looking bike. Too bad it was left out in the weather for a while. Should clean up nicely though & look real good. I like the license plate. ;)

J.

Bucko

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Re: Honda CB900F
« Reply #11 on: January 16, 2014, 09:46:47 am »
Yes, that looks like it will clean up nicely (with just a little elbow grease  ;)).

Be sure to check out: http://www.cb750f.com/