[Real_man]

Originally Posted by kd7202

@ Real_Man,

Better to change the entire bore / piston kit with a new one. The RE workshop will do a rebore of existing bore but may not stand guarantee for the workmanship.

A new bore/piston kit along with piston rings costs about Rs. 4000/- and reboring costs approx. Rs. 2500/-. Go for the new kit.

I was also in the same dilemma. Whether to rebore or buy a new kit. Decided to go in for a new kit. After all, the difference in costs is negligible. Will be getting the surgery done in a few days.

Cheers

KD

Thanks KD. Cost-wise it really make sense to replace it. Lets me inspect the Block as advised by voodoochild.

Originally Posted by voodoochild

Piston rings are the components that hold compression. Loss of compression generally means worn rings. New rings will rectify this. Rebore is generally not required unless the bore has undergone deformities due to some serious wear. How old is your engine km-wise?

Apologies if I'm adding to your confusion. I understand you've got limited time to sort this issue out.


Valve seats?

@ voodoochild: Based on our discussion. I now have couple of option in mind, let me inspect the Block first.

I assumed sleeving of valve would be same as Valve seats. Don't know really if there is anything called as sleeving of Valve channels.

[jeeva]

Originally Posted by Real_man

I assumed sleeving of valve would be same as Valve seats. Don't know really if there is anything called as sleeving of Valve channels.

Valve guides it should be.
I assume by "sleeving", the ASC folks plan to do some machining on the old guides and valves. These are'nt very expensive parts, but are one of the main reasons for clattering sound from the head. Better replace the valves, guides and valve caps; Rocker arms if necessary. Talk to the ASC folks about gun metal guides. The same applies to the tappet valve guides.

[Real_man]

Originally Posted by jeeva

Valve guides it should be.
I assume by "sleeving", the ASC folks plan to do some machining on the old guides and valves. These are'nt very expensive parts, but are one of the main reasons for clattering sound from the head. Better replace the valves, guides and valve caps; Rocker arms if necessary. Talk to the ASC folks about gun metal guides. The same applies to the tappet valve guides.

Great! Thanks Jeeva, I am now well equipment to visit the ASC tomorrow and ask for the things that is needed.

[Real_man]

Originally Posted by voodoochild

Real_man,

Can you click and post photographs of the damaged block and piston?

Rahul

@voodoochild Here is the pic of the Block and piston. I did see some spot wearing out.

I am contemplating on just replacing the piston & see if it works.

[Real_man]

Fellow Bulleteers,

Can I get some feedback on twin silencer Block. I was wondering what if i change to a twin silencer Block.

I was looking forward for a twin silencer look in my bullet.

[Collector]

Originally Posted by Real_man

@voodoochild Here is the pic of the Block and piston. I did see some spot wearing out.

I am contemplating on just replacing the piston & see if it works.

From the looks of piston and bore you will need to have the bore honed to the next size and replace the piston with a suitable sized one. You also need the valve guides replaced as there is evidently oil leaking onto the crown of the piston. While you are getting this work done I would also suggest that you have the oil pump fully overhauled and checked.
Please do NOT go for gun metal valve guides unless you are very sure of the people doing the job. I have had a problem with such replacement guides and now prefer to stick with the cast iron guides.

[Real_man]

Originally Posted by Collector

While you are getting this work done I would also suggest that you have the oil pump fully overhauled and checked.

Please advise if I can upgrade the pump to one in UCE engine, I believe it pumps 3 times than the one in AVL engines.

[ArizonaJim]

The gerotor type oil pump used in the UCE will only fit and work in the Unit Construction RE engine.

Its mounting, oil transfer ports and drive system are totally different.

[abhimanyuargal]

Does anyone know whether a seat transplant is possible from a thunder-bird to a standard? I want to fit a thunder-bird seat on my 78 standard 350. Any tips?

[Blazkowicz]

I fitted my C350 with more than 4000 KM on the odo with a Sans Inc glasswool short bottle yesterday and have ridden about 150 km since. Today I noticed that there are missing beats when the bike is idealing. What could be the reason for this?

[BulZire]

The Carb rings gets worn out and has to be changed for every 4000 kms when you go for a glasswool . that could be the reason for missing beats.
Check this out.

[KkVaidya]

Dear Techies,
I really messed up last week while setting the tappet clearance. I don’t know how but the tappet setting bolt has come Off

Now I am unable to get it back in. The threads have also got worn out probably due the excessive loosening/tightening of the tappets. Will get a replacement but now it’s a really miserable condition as I have to load the motorcycle in a pick-up and take it to the workshop.
Can anyone guide me on how to assemble it again? I have all the tooling on hand so no problem in that regard but i feel the cylinder head may have to be opened to access the valves and lift the Pushrod for fitting the bolt.

[jeeva]

Originally Posted by KkVaidya

Can anyone guide me on how to assemble it again? I have all the tooling on hand so no problem in that regard but i feel the cylinder head may have to be opened to access the valves and lift the Pushrod for fitting the bolt.

1. Remove off the petrol tank.
2. Loosen up the three bolts on the rocker cover and the cover will come off.
3. Unscrew the 4 bolts (on each) rocker arm assembly, diagonally and it will come off.
You can now pull up the tappet rod. Fit the slack adjuster and gently guide the tappet rod into the correct position.
Be sure not to interchange the intake and exhaust rods, anyways, the length is different.
4. When you fix the rocker arm assembly back, be sure to tighten the nuts in a diagonal fashion and ensure that the arm moves freely. Do not over tighten.
5. Start the engine and make sure that oil pumping is good enough at the rockers.
6. Fix the covers and tank.
7. Adjust the tappets. Its wiser to keep some free play, rather than having no free play at all.
Hope this helps.
NOTE: do not kick and change the crank position/timing gear position in between. Hope you have not tried to as of now. If not, best get it done by a good mech as the timing too would need to be set.

[KkVaidya]

Originally Posted by jeeva

NOTE: do not kick and change the crank position/timing gear position in between. Hope you have not tried to as of now. If not, best get it done by a good mech as the timing too would need to be set.

Thanks a lot. Will carry out this operation tomorrow. This way I can at least start the motorcycle & take it to the workshop for setting the timing.
Well for the kicking or changing the crank position, do you mean not to do that while adjusting the tappets or not doing it only while carrying out this particular operation?

[Collector]

It is not a difficult job at all.



1. Remove the petrol tank.
You will see 2 covers held on with 4 bolts each. The one towards the front of the bike is the exhaust cover and the one towards the rear is the inlet cover.

2. Remove the 4 bolts on the rocker cover and the cover will come off.

Remove only the inlet side cover

3. Undo the 4 bolts on the rocker arm assembly, diagonally and remove. Note position, washers etc to replace.

You can now pull up the tappet rod. Fit the new adjuster and gently guide the tappet rod into the correct position.
Now ensure that the engine is at Top Dead Center. Piston fully up. Remove plug. Then switch on key and slowly kick bike or engage 4 gear and turn back wheel forward till the amp meter shows 0.
4. When you fix the rocker arm assembly back, be sure to tighten the nuts in a diagonal fashion and ensure that the arm moves freely. Do not over tighten.

Now adjust the tappet rod so there is some free movement [rotation] and no or very slight up and down movement.
5. Start the engine and make sure that oil pumping is good enough at the rockers.
6. Fix the cover and tank.
That should do the trick
If in any doubt when doing the job feel free to call me on 9344833274 and I can talk you through it