CG125 OHV Build Oddessy

[crazypj]

Re: CG125 Maiden run sore arse plug chop.

Plug looks OK, little rich but heat range OK (check colour of ground electrode as well as porcelain)
You could probably lean it out sightly, fit cooler running plug, and get a little more power.
BTW, damn good close up 8)

 

[Erskine]

Re: CG125 Maiden run sore arse plug chop.

Plug looks OK, little rich but heat range OK (check colour of ground electrode as well as porcelain)
You could probably lean it out sightly, fit cooler running plug, and get a little more power.
BTW, damn good close up 8)

I tried your suggestion PJ, and lowered the needle, it is now one notch LEANER than stock settings.
Result: flat spot completely disappeared and pulls like Jordie lad out on the razz.
I'll do a plug check when I've had a spin on it later.
It is currently running a NGK DR8EA which came with the bike.


I also removed a high spot on the brake shoes which seems to have reduced the front end vibration a little, and although the front brake lever feels less 'firm' the forks now compress alot under braking, so I assume more surface area of the shoes is coming into play.

 

[Erskine]

Re: CG125 Getting there.

Hooned it up the S-bends, a local hairpin climb up a mountain pass, taking it to 6000 rpm in each gear.
Jeeeeeeeezus it pulls cleanly now. The tramping in the front end is all but gone as well.
Climbing is fun ........ Completely crapped my self coming back down.
That's the highest I've revved it so far, dunno how fast that equated too, not very I suspect but quite enough on wooden cheng shin tyres.

The roads are a bit like this (don't cry PJ)

http://youtu.be/RehhFFmHzY0

 

[Erskine]

Re: CG125 Oh no not the comfy chair.

I need to civilise this puppy for day to day use, so I'm working on a second set of clothes, which will also give me a chance to tart the race wear up. So I broke out the Ply and staple gun.

http://youtu.be/XnS49c9KZw8

 

[baconpocket]

Re: CG125 Oh no not the comfy chair.

is that just half of the old seat? lol, i like the plastic one better, but that's a good use of old parts

 

[Erskine]

Re: CG125 Oh no not the comfy chair.

is that just half of the old seat? lol, i like the plastic one better, but that's a good use of old parts

It's the foam of the old seat heavily thinned and shaped with the back half of the seat cover stretched over a ply base. I like the plastic one too, it gives a great racing position and I'll be tidying it up now.

 

[stik70]

Re: CG125 Oh no not the comfy chair.

Great to see it getting used and working correct! You live in such a beautiful area. I am surrounded by corn and soybean farms. Hope you put loads of miles on it this year. Sometime we'll have to talk about trials.
Kev

 

[Erskine]

Re: CG125 Oh no not the comfy chair.

Great to see it getting used and working correct! You live in such a beautiful area. I am surrounded by corn and soybean farms. Hope you put loads of miles on it this year. Sometime we'll have to talk about trials.
Kev

I know I'm going about this back to front compared to most builds on here.... but from the onset the plan was function first. We're surrounded by crap land, destroyed by 100 years of mining and fit only for sheep!
Give me a bench seat column change F250 and corn fields stretching out to the horizon.
What trials are you thinkng? PM me.

 

[crazypj]

Re: CG125 Getting there.

Hooned it up the S-bends, a local hairpin climb up a mountain pass, taking it to 6000 rpm in each gear.
Jeeeeeeeezus it pulls cleanly now. The tramping in the front end is all but gone as well.
Climbing is fun ........ Completely crapped my self coming back down.
That's the highest I've revved it so far, dunno how fast that equated too, not very I suspect but quite enough on wooden cheng shin tyres.

The roads are a bit like this (don't cry PJ)

http://youtu.be/RehhFFmHzY0

Glad you got rid of flat spot.
You could try going up a grade to a DR9EA which runs a bit cooler
Other than that, damn, you got me :'(

Which set of 'S' bends, Llangeinor or Blackmill? ;D
Great piece of film, is it the one that was filmed in Garw?
Looks like going over the Bwlch down to Treorchy, doesn't look like its changed in 13yrs 8) (hell, it probably hasn't changed much in 60 yrs ;D )

 

[Erskine]

Re: CG125 Oh no not the comfy chair.

Glad you got rid of flat spot.
You could try going up a grade to a DR9EA which runs a bit cooler
Other than that, damn, you got me :'(

Which set of 'S' bends, Llangeinor or Blackmill? ;D
Great piece of film, is it the one that was filmed in Garw?
Looks like going over the Bwlch down to Treorchy, doesn't look like its changed in 13yrs 8) (hell, it probably hasn't changed much in 60 yrs ;D )

It was filmed in the 90's I think, it's the Bwlch, the Ogmore and the Garw, but all edited up in a un realistic order, one minute he's going up through Blaengarw and the next he's going down through Pont etc.
Very little has changed over Treorchy, but you would be stunned by the Garw now.
But it still rains 90% of the time.
The S bends I went up were the Llangeinor ones, I turned at the Arms and came back down again.

 

[Erskine]

Re: CG125 Royal Wedding Special

Well, us Brits really do know how to put on a good bash
And I fitted a new chain. Genuine Honda DID old stock.
Now there's an improvement!
Sprockets are 75% condition, I intend to lower the gearing a tiny bit in the future so I didn't was to buy new ones in this ratio, but the chain had rapidly reached the bloody dangerous category an it was a no brainer.

So far I've saved so much in fuel costs, the bike has paid for the cost of the road tax already.

 

[Erskine]

Re: CG125 Reality check

Shamone Muckers!

A little update and a few conclusions:

I've been riding the bike daily as my main run around for local bimbling.
I'm easily getting 120 - 130 mpg, which is saving me a fortune.
The engine is very reliable, even without a kick start and bumping it all the time ...... as soon as the engine revolves it fires up.
If you've read through this build you'll see I put my time and dollar into reconditioning the mechanics of the rolling chassis:
I.E. all the bearings inc head races, suspension and brakes. This has made a massive difference to that crock of crap I started with, infact, for what it is, the front end is very good - I really like it. I think with some decent modern tyres on the bike it would be even better. Lced to some lighter and wider rims would be awesome.
The engine in it's mild state of tune is quite enough for the limitations of the bike and I'd rather the inherent reliability and rideability.
I found that although having the seat and rearsets way back gave a great racing position that was ergonomically sound, it wasn't optimum weight distribution for the rear suspension to contribute.
Likewise the rear sets. Both need to move forward about 3 ", which give a more cramped 'small bike' feeling.

Since the next hill climb race is not till October, and the race position is not condusive to running errands and unmade roads, I'm working on a second set up for it ...... more trialsy. This also gives me a chance to work on tidying up the seat and tank.
I've got a lovely little SL125 tank to go with the trials pad, along with the choice of a 19" or 21" front wheel.
A sweet little chrome 5" headlight for the winter was given to me.
I have a small budget for rubber which will go on trials tyres for now. I'd like to get a late CG 18" rear wheel so I have one set of wheels 18 & 18 for racing and another set 17 and 19/21 for general valley use.
I'm just about to fit a 45t rear to replace the 38t. with the 14t front this will give the same gearing as an XL125. If it's too low I'll put a 15t on the front which will take it back up, but if I want to go lower, to stock TL 125 I'll go down to 13t. So long as I can pull 35 - 40 mph comfortably I'll go as low as I can.
Competition TL's used to use 15t/60t but now the in vogue set up is 12t/60t! It was common to swap the CG OHV engine in place of the OHC unit because the CG has such low down torque and I can see why.
So I'm quite interested in exploring this.
Plans .....
I'm having the foot levers cranked out from the plate, this will allow me to move them as far forward as I can, which will give a good trials position and also a better weight distribution as a racer.
Buy a kickstart!
Paint the SL tank red
Move the seat pad forward a little
Fit front wheel/trials tyres
Trials bars
Plastic one piece rear mudguard.
I want to refit the rear triangle, it's badly put on so I'm going to grind it off, and reweld it an inch forward and an inch lower. This will lay the shocks down a little and help them work better.
Bend up a new header to run a high level system
I'd also like to reposition the tacho, right down by the engine!

So still a work in progress really, but earning it's keep big time.
I'll start to make it look better as it evolves, so glad I had resisted peppering the rearset plates!

 

[Erskine]

Re: CG125 Reality check

What kind of sprocket combinations were you running?

The first tank I bought off Evilbay was a bit of a mistake, It looked like more of a peanut tank but when it arrived it was friking HUGE, I mean like a good 3 Gallons.
So I'm reselling it, and picked up the SL tank for half the price, with tap and cap! TL tanks go for stupid money.

 

[honeybadger]

Re: CG125 Reality check

this is a very.... interesting bike build.


But I have to say, that new tank really just does something for me. Really digging it now.

 

[Erskine]

Re: CG125 Reality check

this is a very.... interesting bike build.


But I have to say, that new tank really just does something for me. Really digging it now.

Cheers! It's evolving in it's own time! It was never going to pretty straight off, bit of an ugly duckling.
However it is 100% mechanically sound and road legal.
I like the new tank as well, it's a nice shape and not too bad condition, I actually think it is quite a rare find in the UK and I was surprised to get it so cheap

Thanks for that info Glenn, that sprocket combination covers a multitude of options.

 

[Erskine]

Re: CG125 Reality check

Woo hoo! The tank I bought in error just sold for more than I paid for it
Does that mean I've become a capitalist?

 

[Ringo]

Re: CG125 Reality check

Scalper?











;D

 

[Erskine]

Re: CG125 Cranking

Sooooooo Muckers.
I'm still working on the trials alter ego of the bike and generally enjoying zipping about the 'hood.
Finally obtained a new kickstart lever No more undignified bumping.
I've also had the foot controls cranked out, much more positive operation now, also I can move them forward a few inches and clear the rearset plate bolts.
The 45t sprocket is now on paired with a 14t front and I'm still testing the ratio. 1st is now a real granny gear which I'm liking, the question is whether 5th is still going to be high enough to live with.

 

[Erskine]

Re: CG125 Evolving

Quick Bank holiday update:

I've primed the SL tank red and rebuilt the petrol tap. It's surprising how much better quality design and build the 70's stuff is. It took a few flushes to move the crud from the tank and a two pack chemical lining will be in the future.

I've been given a 19" XL 100 wheel (late 70's I think) but it has 3 spokes missing. Damned if I can get 3 spokes for it. If I can't find ant I'll have to look out for a 21" but I think I'd be nearing the clearance limitations on full compression
Any suggestions on the spoke front?

So I'll be going for a 17"/19" combo as trials wheels, and I'll look out for a late CG 18" rear wheel to pair with the 18" front for road use. My 18" front has a 130mm drum for some reason, as opposed to the usual 110mm drum on this family. It must be one of those anomilies but I'm not complaining because it's efficient

I've put on a 15t front sprocket so now the bike has a completely new drive train. It was just that bit too low for pootling about. 1st gear is not as much fun any more for crawling but 5th is much better on the road and the chain should wear better. The 14t I've taken off is very good condition and it's only a 5 minute job to swap it back when wanted.
As standard this model had a 2.7:1 rear drive ratio, with the 14/45 combo it had a 3.2 ratio and with this 15/45 it has a 3.0 ratio.

This week I've got some workshop time and the plan is to bend up a high level header, and shorten the rear brake pedal so it fits my foot better. I'm also going to take a saw to the original sprocket cover and chop it about to accomadate the gear linkage and refit it.

I also want to get a multimeter on to the gennie wires to find out whats occuring. And order an universal rear brake light micro switch.

I'll get some photo's up when it stops freaking raining. It's like winter again!

 

[Erskine]

Re: CG125 vs the bathroom scales

Well, Ringo's weigh in made me inquisitive.
Dry weight standard - 251 lbs which is 114kg in new money
Wet weight now - 185 lbs or 84kg with 1litre of oil and 2 litres of petrol on board.
That's a whopping 66lbs of excess fat most of which I suspect was the starter motor and centre stand!

Here's a photo of it now looking a bit trackerish.