NEW PROJECT (BUT NOT A THUMPER)

[xbally]

The starter has now been fully refurbished by my mate and bench tested. He's also made me some new leads.New solenoid should arrive tomorrow.
Hoping to have the bike ready for the MOT I started to bleed the brakes but a seal has gone in the master so more work to be done....

[Moto63]

Blimey Martin, it seems to be two steps forward, one step backwards for you with that bike. Still, keeps you out of mischief eh 😉. Plus, I’m sure once it’s finished and road worthy and you’re whizzoff down the road on it, the sun shining down on you, birds tweeting in the trees. Life will feel just dandy.
Best of luck with the MOT 🤞
Cheers, Michael

[iansoady]

You know of course what the problem is - it's not a Thumper!

[Moto63]

You know of course what the problem is - it's not a Thumper!

😮…..that’s it. You’ve nailed it Ian
May that 4 cylinder machine be cast out and struck down by lightning ?? 😁

[xbally]

It's transitioning into a thumper slowly
.....will only run on 2 cylinders.....

[Moto63]

It's transitioning into a thumper slowly
.....will only run on 2 cylinders.....

Holy shamoly Martin, do your woes never end with the little 400 😔
I suppose it’s a case of  chin up & carry on eh.
Best of luck with the remaining two cylinders 🤞🤞
Cheers, Michael

[xbally]

Thanks Michael.

At least my mate was able to recondition the starter motor so it's like new.

It and the new battery and solenoid got a good workout when it took me half an hour of messing about with Easystart to even get the motor to run albeit on just the 2 pots.

[xbally]

No chance of getting this thing MOT'd at the moment......

The front brake was easily fixed. My friend suggested trying a Chinese master cylinder off eBay, they are only £10 post free incredibly.

Looking through my spares I had the feeling I'd already got one and lo and behold, yes I had. Bought for my 750 Monster about 2 years ago but the mirror mount was wrong so I never fitted it. It bolted straight on and bled up almost immediately. I think I paid about £30 - £40 but it seems to work very well though not tested on the road yet.

I'm now going through the ignition system which isn't easy. Coils seem almost impossible to get at .I've already encountered problems with spark plug threads as earlier posts show.

Upon checking the carb to head inlet rubbers they are cracked and hard as rock so they are going in the bin as fitting the carbs has become increasingly difficult-I must have had them on and off at least 10 times!. Fortunately China has come to the rescue again with new ones at £10 a set. Hopefully they will do the trick but the airbox rubbers are just as bad and the only new ones I can source at the moment are from CMSNL in Holland.............

[xbally]

Inlet rubbers fitted and carbs back on.
Plugs all now sparking on the head when earthed so reinstalled those and fitted caps.
Now running on 2 cylinders so am checking fuel in float bowls to the offending cylinders carbs.
Using a remote fuel supply to bypass the tank and tap.
Am also going to bypass the pump on advice from my mechanic friend.
Whether progress will be made who knows...time will tell.
Otherwise it could be time to source new coils etc
..

[xbally]

I'm still battling this foe big time...
I managed to get a rubber seal from the end of a new NGK spark plug cap stuck down the deeply recessed plug aperture in the head which meant I couldn't get access in the very limited space to remove the plug.
I had to order some long pics as mine wouldn't reach far enough to hook the seal out.
Now I can't get the engine to fire at all.
The carbs have been removed again to clean out the pilot jets and I'm informed modern fuel has more than a propensity for fouling spark plugs especially on a four for some reason.
The latest debacle is that I can't tighten up the carbs on the inlet stubs sufficiently  due to the old and worn mounting clips, the screws for which have been butchered by years of use of the wrong type of none JIS Phillips  screwdriver so I've now had to order new screws and raid my spares cache for replacement clips.
This project is now beginning to look like one of those never ending ones that used to regularly appear in classic bike magazines of a few years ago.

[iansoady]

... and those projects usually mysteriously disappeared never to be seen again.

This'll teach you to abandon singles Martin!

[xbally]

Yes Ian, I fear you may be right although I haven't completely abandoned singles as I still have my Honda CB250RS and Royal Enfield Guerrilla 450. They are like chalk and cheese of course one being fairly ancient and the other modern.
I have to say the RS has been pretty reliable although I don't do too many miles on it these days.I used to do at least 1000 miles a year, now I think it's more like 500.

Perhaps I should take up the GN250 that's been offered on here as my new project  and ditch the overly complicated (by comparison) 400/4?

[Moto63]

Yes Ian, I fear you may be right
Perhaps I should take up the GN250 that's been offered on here as my new project 

To quote the great Arnie in the film predator “DO IT, DO IT NOW”
You just know it makes sense Martin. It would also mean the mighty midget may just ride again 🤞👍

[iansoady]

I agree. Nasty things those Honda 4s.

[xbally]

I agree. Nasty things those Honda 4s.

I've had a few and this is by far the worst ....several of the old 400/4 air cooled (75-77), a 1981 CB900F and a 95 CBR600F-that was pretty troublesome too. The problem is IMHO degradation of rubber and plastics combined with modern fuels..........