Honda CX 500 Forum banner
41 - 60 of 735 Posts

·
Registered
Joined
·
832 Posts
They look so good that I would leave the covers off !
 

·
Super Moderator
Joined
·
23,060 Posts
Discussion Starter · #47 ·
I thought I'd record here for those who haven't seen it before how I do the 'hogout' for mechanical seal replacement on the early {prior to sometime in 1981} CX500 fitted with the 27.8 mm mech. seal and preparing the rear cover for fitment of the 28.3 mm seal that is available now, such as the Yamaha seal and the AES seals that I use.

Anyway, first up you need to pry out the oilseal.

Auto part Tire Wheel Automotive wheel system Automotive tire

Winkle this out a little carefully, you'll be wanting it again.

Now flip the cover over and knock out the mechanical seal with a large, close fitting drift or piece of pipe. You don't want to deform the seal, you'll also be wanting this again.

Auto part Bicycle part Engine Machine Automotive engine part

Tap the oil seal back in flush with the housing.

Auto part Metal Steel Machine Engine

This is now your depth stop and will prevent the oil seal area from being hogged out.

Auto part Wheel Automotive wheel system Rotor Rim

At this point the new seal does not even look like fitting - it just sits on top of the hole laughing at you.

Auto part Bearing Automotive wheel system Wheel Hardware accessory

The original seal also does not fit back in - but it's 'lead' does - and this is what you want the new seal to eventually look lie sitting in the hole.

Auto part Bearing Clutch Hardware accessory Wheel

Now, start to dremel the hole.

Auto part Engine

What you are initially looking for is for the original seal to be a drop in fit back in its hole with a minor amount of free play.

As soon as you can detect any play it is enough and time to put away the dremel. {I actually run the flap wheel in a drill, dremels don't have a lot of torque}.

Auto part Bearing Wheel Hardware accessory Metal
 

·
Super Moderator
Joined
·
23,060 Posts
Discussion Starter · #48 ·
At this point, the new seal will start to 'lead' in, ready to be pressed.

Auto part Bearing Wheel Metal Hardware accessory

I urge you, once you have the original seal as a drop in fit to begin to go incrementally for the 'slop' to use both your old and the new seal for checking your progress and use your judgement. Once happy with your work knock the oil seal back out.

Auto part Engine Carburetor Machine Automotive engine part

Now you can inspect your work and press in the new seal. I won't be pressing the seal in just yet as I have more cleanup to do on this cover - but I know the seal will now fit. I've done a few this way now.

Auto part Automotive wheel system Wheel Rim Auto part Rim Automotive engine part Wheel Metal Close-up Auto part Photography Macro photography Audio equipment
 

·
Super Moderator
Joined
·
23,060 Posts
Discussion Starter · #53 ·
I have my crankshaft and rotor back now. The rotor has been lightened by 625 grams.

If I get the chance tomorrow I will take a block and liner to a local engineering shop that perform this sort of work {resleeving} tomorrow.

In the meanwhile I have been preparing some rear covers. One for the thingummy with a new G8 stator, output shaft bearing and seal and Raesan hall effect. Also a new neutral switch.

Another for general use with a good used OEM stator which is still mostly light brown in colour and has good resistances. This one also has a new output shaft bearing and seal. This one is also set up with a good pair of stock pickups and advance coils and is compatible with stock CDI if a Raymodule power supply is used, ignitech or non hall Raesan. Good used neutral switch.

I have two more rear covers in the works. All have been hogged out ready for new mechanical seals.

I have ordered the two exhaust valves I will need to rebuild the thingummies heads from David Silvers along with two valve clearance adjusters and 8 green rod bearing shells. The postage for this massive package? Just short of $80 for this order - and then hit with a $11 foreign funds fee. {government? bank? - who knows.}

Am also doing a bit of a shed cleanup again, though not on the scale of the last one which took months. And adding some more lights down the back part and over the bench that I never actually got to last time.

I have a new thermostat to put in the CX I am currently riding for winter as I suspect from its warm up time that the existing one isn't closing. Will get to this soon.
 

·
Super Moderator
Joined
·
23,060 Posts
Discussion Starter · #55 ·
A little action on a couple of things.

The CX I'm currently riding has been running very cold. A few days ago I fitted a new thermostat and checked on the 7 volt regulator. The 7 volt regulator was outputting 7.08 volts - normal. However, just in case it's figures changed once it had been powered for a while I fitted another with an output of 7.04 volts.

Checking at the sender I see 6.45 volts so checked and cleaned all connections. Still 6.45 volts at the sender. Further checking shows 7.04 volts into the temp gauge and that same 6.45 volts coming back out.

I checked the resistance on the gauge and get 38 ohms. I guess this is the source of the voltage drop. I also guess it must be normal as I got the same 38 ohms resistance on two spare temp. gauges.

I may try another sender just in case.

While I was in the headlight I took the opportunity to clean all the connectors and do a general tidy up

I've just been to pick up the resleeved block from Southcotts and the bike actually did reach full temperature on the way back, so some improvement. I need to ponder this a little more.

Will likely detergent wash the resleeved block later today so I can start building this motor once I have the chance.

I'll upload some photos soon.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
17,244 Posts
It works by the series voltage divider principle: It you connect 2 resistances in series the voltage across each of them will be proportional to the ratio of the resistances (e.g. if you connect a 60 ohm resistance in series with a 40 ohm resistance and apply 10V the 60 ohm will drop 6V and the 40 ohm will drop 4V).

The gauge is actually a voltmeter that is permanently connected across a resistor and the sender is a variable resistance so as the sender's resistance increases the gauge reads lower and as the sender's resistance decreases the gauge reads higher.
 

·
Super Moderator
Joined
·
23,060 Posts
Discussion Starter · #57 ·
I checked an online calculator for that. It requires two resistances to be added to the fields. so I put in 37 and 1. It gave a power output from 7 volts at .085 volts.

I may have ####ed up by unbalancing the figures .....
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
17,244 Posts
The red is what I originally said. It is incorrect because I misread and thought that the sender was 38 ohms, not the gauge.


You know the resistance of the sender (Rs) and the voltage (7.04V). Measure the resistance of the gauge (Rg)

Rs / (Rs + Rg) x 7.04 = Voltage across sender.

I'll bet the gauge resistor is close to 3.48 ohms.



Here isd what I should have said (see post #66)

You know the resistance of the gauge (Rg) and the voltage (7.04V). Measure the resistance of the sender (Rs)

[Rs / (Rs + Rg)] x 7.04 = Voltage across sender.

I'll bet the sender is close to 415.4 ohms when the voltage across it is 6.45V
 
41 - 60 of 735 Posts
Top