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Bought a CX500. Turns out the engine is 395 cc - help me identify my bike!

10K views 28 replies 9 participants last post by  guelli02 
#1 ·
Hey guys.

This summer I bought what I thought was a cx500 custom. As it was my first bike ever I didn't really consider it a possiblity, but having a closer look it seems like it is a bike put together. As I want to restore what I can on it I need som help identifying it. I have had a close look in the forums but cant really find my specific VB number, so now I am asking here.

This is what I have found out:
- The engine is a 395 cc, not a 500cc.
- The front forks are similar to the sketchings of GL500 forks (found in my Haynes manual while rebuilding)
- My carbs are numbered VB 35A + (sign I cant read) + QD.

I will try to post a picture of the bike and the carburetor.

What I want to know is:
- Are there specific parts for the engine or can use parts from a CX500 (of ebay etc)?
- The carbs need a rework (I orderer larry's guide) - what kit should I buy?
- Anything else I might want to know conserning a bike like this.

The bike has definetly been tampered with and the parts are all in all pretty rusty.

I am looking forward to your response guys :) Help is much appreciated Land vehicle Vehicle Motorcycle Car Motor vehicle
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#2 ·
you are over seas

so depending on where you are it could have been sold as a gl400

or a cx400 shadow

the interesting part is it has what would be a standar rad shroud (dont put much in that honda uses up parts)

the forks look right dual disc was common everywhere but north America

what are the serial numbers stamped into the right side of the neck to will have to look carefully for them as they paint over them
 
#3 · (Edited)
Thanks for the quick reply!

The bike is currently parked 30 min from where I live, so I cant tell you right now. However, I have the picture of the registration stamp posted below if that gives you any clue.
Looking through some om my photos of it I however found that it most likely is a GL400 E engine (see pic below). Does this match with carb VB number?

The weird part is that it is registered as a cx500 on the frame aswell as on the papers I have on it.

Do you know if parts are interchangeable?

I live in Denmark by the way

Auto part Vehicle Car Wheel
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#4 · (Edited)
You have a VIN plate on the right side chassis rail below the side cover read the information from that. Agree with Murray it has a 78 rad and surround which has obviously been replaced at some point. The engine CC can be identified by the square cast indent in the left side cylinder block above the water transfer pipe.
Looks like it has a 78 brake master cylinder as well.

edit, just saw your pictures the frame number suggests it's a 78-79 CX 500 which has had an engine transplant at some time, I think the carbs are 500 ones also.
 
#6 · (Edited)
I'll have a look at the VIN plate you guys are talking around tomorrow. Thinking back on the purchase, I think the seller told me it has the radiator of a CX650

@ Murray: Engine parts aswell? Also: Specifically concerning the carb; I'm thinking of ordering the randakk rebuild kit - How do I know if the carb has a accelartor pump when I dont know the specifics of the MC?

Edit:

@trev: Do you know if this has a influence on the overall running of the bike? My papers says it has been registered first in 79
 
#8 ·
It is probably a 79 CX500, a CX 400 would say so on the vin plate along with the engine capacity, a custom frame would start with PCO1, I suspect it has just had a 400 engine put in it, a swap to a 500 motor would be simple, I think the carbs are 78-79 500's with the early type cut offs.
 
#9 ·
It seems to be a CX500 frame.....but the frame number doesn't start with PC01

But a lot is modified:
reverse ComStar wheels, fuel tank, front fork, front and rear lights, seat (King&Queen (?)), ...


... the only 78/79 part is the round brake fluid reservoir and the radiator shroud (but without refelectors ?).

IMHO it's a puzzle bike.
 
#10 ·
@ Trev @gueli02 sound pretty reasonable - good job guys! Its nice to know what I am dealing with here. Is it common practice to swap out parts like this?

@ Larry I'll get a pic for you tomorrow. I dont want to order the wrong stuff.

Should I be concerned about the parts having been switched like this? So far it runs OK. As mentioned the carbs needs cleaning, but the motor (from a beginners POV) seems to be running alright.
 
#11 ·
No, I wouldn't worry if it runs fine accept it for what it is, I don't think after 30 odd years there are many bikes totally original and many have had parts from other bikes.
I think mine has parts from every model they made but thats how it suits me, what ever it is though service it and maintain it and it will be fine.
 
#16 ·
Vin plate is 78 CX500. It appears to be pop rivetted to a custom frame. Beware.
I saw the rivets, but was to lazy to go down to check how it is made on my CX and CXC.

The last check will be to look on the right side of the steering head and compare the numbers.

But I know to "change" / to "correct" with the right stamps / punches a frame number :cool:

We say: Don't wake up sleeping dogs ;)
 
#18 ·
Thanks for the replies, guys! I have looked at the neck of the bike and the numbers match with the plates in the previous picture.

@gueli02 Are those the only parts that may differ from carb to carb? As mentioned I am thinkning of buying a kit rather than the parts seperately. Thanks for link by the way. It seems that there are some parts of the motor that I can use from the CX500 motor.

@Murray I've posted some pictures of my carbs taken while they are still on the bike. Can you see whether they have the acceleratorpump from those?

Auto part Automotive engine part Engine
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Auto part Fuel line Automotive fuel system Engine Vehicle
Auto part Tire Automotive wheel system Automotive tire Synthetic rubber
 
#21 ·
@Flogger What does "sold naked" have to do with the Honda badges? :)

After doing som reading on a CX500 forum from Australia I found a mention that the carb VB 35A refers to 35 mm. What are those 35 mm? At this point I'm a bit confused whether it is possible for me to buy a carb kit, if I should buy parts seperately or just clean the parts I have as it is described in Larry's carb book.

edit:

found the link for the mentioned article here

http://www.australiancx.asn.au/forum/index.php?topic=11766.0
 
#24 ·
I found a mention that the carb VB 35A refers to 35 mm. What are those 35 mm? At this point I'm a bit confused whether it is possible for me to buy a carb kit,
I think the carbs VB 35, VB 36, VB 39, VB 26, VB 23..27...29 etc. are just types and no sizes.
But for the VB36 I measured 36mm in the middle of the venturi part.
That place/region where the vacuum piston in the carb body sits.
 
#22 ·
Naked means without the fairing and luggage bags as stock equipment.

Please edit your profile to include your location, someone may be near by to help more. Also add to your signature line your bike details so we always know what to look for.

Joel in the Couve
 
#25 ·
The number on the carb refers to the size of the throat of the carb.
Different sizes allow the company to meet emissions requirements in various locales.
They also mean that you would have to jet them differently as well.
Typically smaller bore carbs will be used with lower cc engines and those with restrictors in the exhaust to reduce power.
 
#27 ·
Maybe with the stock carbs, in the application I am more familiar with, Mikunis are used and the number refers to bore size and the letters after refer to needle configuration.
So I stand corrected and learned something new today.
 
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