From 107 to 128

[VTRDark]

Where it's tight just loosen one or two of the cam cap bolts ever so slightly.

[freeridenick]

Not all cams are the same size and can be loose or tight .
As it’s tight (good news ) you’ll have to lap it in .
As for the sprockets ,they were off a good engine .

I hope there was no offence taken. There was none intended.

Having just looked at the heads I'm a lot happier. It's the rear intake cam that's tight and since these never (near enough) have a CCT failure I'm confident it's not bent. Out with the plastigauge tomorrow.

[StormyRob]

Just saying nick

The bike I had brought over from England had a rear cct failure.

I hope it all works out mate

[freeridenick]

This weekend was a long one but fruitful. I was up at 3:30 to take my partner to the airport so I’d worked out the cam problem before dawn. One of the journals was a bit tight and checking the cam in the exhaust journals it span freely. No bent cam.

It still took a couple of hours, a good proportion of which was spent guzzling coffee, with constantly checking the clearance as I didn’t want to go too far. Making sure the polishing/grinding paste I’d forgotten I had was all cleaned out took a while too. I finally got the Heads on the engine and off to the garage just after lunch. The rest of the weekend was spent repairing and filling bodywork, and modifying the airbox.

[sirch345]

This weekend was a long one but fruitful. I was up at 3:30 to take my partner to the airport so I’d worked out the cam problem before dawn. One of the journals was a bit tight and checking the cam in the exhaust journals it span freely. No bent cam.

It still took a couple of hours, a good proportion of which was spent guzzling coffee, with constantly checking the clearance as I didn’t want to go too far. Making sure the polishing/grinding paste I’d forgotten I had was all cleaned out took a while too. I finally got the Heads on the engine and off to the garage just after lunch. The rest of the weekend was spent repairing and filling bodywork, and modifying the airbox.

That's good news, well done Nick

You certainly don't want any grinding paste or polish left behind that's for sure

Chris.

[fabiostar]

great news nick . airbox mods? do tell

[freeridenick]

More woes. I picked up the engine last night and one cam is still tight. 20:20 hindsight is great but I didn't think about it at the time. When I lapped in the cam I thought I could get away without taking the valves out as the cam rotates more than 180 degrees but it definitely tightens up once the cam engages the spring. All the other cams are easier to rotate through their full rotation, just the rear exhaust cam goes stiff then releases once the valve is closing.

So that's the Dyno session cancelled, track day cancelled and me on a break from this for a bit. Although by the time I get up tomorrow that might want to get straight back on it. I'm hoping for an oval journal that an engineering shop can sort but there's a possibility the cam is bent. Either way the cam is coming out for proper measurements and I've probably wasted a new head gasket.

[sirch345]

You'll get there Nick, don't panic,

Chris.

[StormyRob]

More woes. I picked up the engine last night and one cam is still tight. 20:20 hindsight is great but I didn't think about it at the time. When I lapped in the cam I thought I could get away without taking the valves out as the cam rotates more than 180 degrees but it definitely tightens up once the cam engages the spring. All the other cams are easier to rotate through their full rotation, just the rear exhaust cam goes stiff then releases once the valve is closing.

So that's the Dyno session cancelled, track day cancelled and me on a break from this for a bit. Although by the time I get up tomorrow that might want to get straight back on it. I'm hoping for an oval journal that an engineering shop can sort but there's a possibility the cam is bent. Either way the cam is coming out for proper measurements and I've probably wasted a new head gasket.

Ah mate it seemed so promising too! Some work gone into this bike so I am sure after a break you wont be able to resist getting stuck in again and having her sorted once and for all

[tony.mon]

I've had similar situations, if you have all of the cam cap bolts torqued correctly try loosening one at a time to see if the cam releases.
If it does, try (carefully) tightening the others slightly and leaving the identified one looser than spec.
They can't fully undo as the cam cover prevents it, but check as I'm working from memory.

One thing is that the head gasket will probably be ok to reuse, as they seem to release again if the engine hadn't been run.
I always use a light touch of oil on a head gasket just in case you need to release it again before running the motor.

[freeridenick]

After weeks of being busy with other activities I found some time this weekend to get in the garage.

Having taken both heads off, removed all the valves and checked the cams they all freely rotate when torqued up. No sticky spots or tightness on any of the cams. The valve springs were all correctly installed and their seats fine too.

Now it's all back together and, after getting the timing 180 degrees out on the rear head, just the same as it was before. Perhaps marginally better, but still with the 'tightness' as the rear exhaust cams start to act on the springs.

I'm going to give Roger a call in the week but I'm pretty much certain there's nothing wrong. I think it's just how it should be given the front intake cams are close to max opening at the time the rear exhaust valves start to open. That's eight springs compressing when everywhere else in the cycle there are only four. Given that the cams have approximately 1mm more lift than stock. the springs will be that little bit more compressed and therefore the engine will feel harder to turn over. At least that's my theory in light of no other issues.

[freeridenick]

The bike is coming together now having snatch the odd hour or two here and there. This weekend should see it all sorted.

I finished off the airbox today and the fuel pump should be wired in early doors along with the carb rubbers after being matched to the ports. Then it's all plain sailing. I hope.

Modified airbox

[fabiostar]

starting to see light at the end of the tunnel now Nick

[sirch345]

Good luck with it Nick
I hope it all goes well from now on,

Chris.

[freeridenick]

Another day and...... IT'S A RUNNER!

There are a few little jobs to do to get it track ready but nothing major. So first thing tomorrow I'll be on the phone booked a Dyno setup.