To do or not to do?

[Bryanj]

Last 400 i did i had to remove a primary shaft bearing(bigish circlip) to move the spacer to allow the strter clutch assembly out, you dont need to do that on the 500.
Apart from that my hands are too big to get in to play with rollers, pins and springs.

Always a good idea to check out the cam chain tensioner horseshoe anyway, if the oil has been bad enough to do in the starter whats the pivot like?

[Otis]

Many points acknowledged there, thank you.
Perhaps a life of kick starting is not such a bad choice in the end?

[Laverda Dave]

I had to buy a bigger pair of circlip pliers to get that out last time I took a 400 apart. My normal SP circlip pliers just didn't have the strength in the handle, it would actually twist with the pressure. You don't want to be in way of it either if it lets go!
As for the cam tensioner horseshoe, I've never seen one that hasn't had some chain damage. The one sold by DSS is an excellent replacement having a proper pivot pin fitted, a shame the guy who makes them in South Africa and who is a member on here is unable to sell them direct due to the postage charges involved.

[Otis]

I had to buy a bigger pair of circlip pliers to get that out last time I took a 400 apart. My normal SP circlip pliers just didn't have the strength in the handle, it would actually twist with the pressure. You don't want to be in way of it either if it lets go!
As for the cam tensioner horseshoe, I've never seen one that hasn't had some chain damage. The one sold by DSS is an excellent replacement having a proper pivot pin fitted, a shame the guy who makes them in South Africa and who is a member on here is unable to sell them direct due to the postage charges involved.

Having grown up in South Africa in the 1970's I would very much like to know who the SA chap is?

[Bryanj]

It amazed me but the last 400 had black treacle inside, shot bores, bad valves but an undamaged horseshoe and pivoted fine----both retaining bolts needed helicoiling though!

[Otis]

I've picked up a lot of mixed messages along the way and would love some clarification but only in respect of the 350/4 because I do know that the 500/4 and the 400/4 are different as is the 350 twin.

1) Has anybody actually taken a 350/4 engine out?

2) Has anybody actually done a Starter Clutch repair on the 350/4?

3) Can the starter Clutch actually be repaired/removed/overhauled with the engine in place?

4) What are the problems that arise during the process; I picked up earlier that the timing chain can be a problem?

Thank you
Graham

[honda-san]

I've done a few over the years, both 350/4 and 400/4 (re-built one of these last week). 350-4 and 400-4 are identical in terms of the primary chain / sprocket / starter clutch arrangement.
Whilst you can remove the primary shaft from the engine with it in situ, the primary gear, etc, is still "inside" the primary chain itself. Only way to get this out is with the lower crankcase removed - which of course means removing the engine itself.

No real problems (Haynes manual is pretty good for these), other than maybe previous owner bodges / poor maintenance, and the fact that these things are approx. 50 years old.

IF maintained properly, the 400/4 in particular is an exceptional bike. My current hack (only used in the winter these days) now has over 125,000 miles showing - and still on original pistons / rings yet does not burn oil. The cam chain and primary chains in it have now done over 95,000 miles since being replaced - and do not rattle. 350/4 is a slug in comparison and needs to be worked hard to maintain A-road speeds.
Only persistent problem has been oil weeps from the camshaft oil feed through the head gasket (every 25,000 miles or so), due to the use of crap (and expensive!) sleeve type seals around the oil jets. I am trialling a modification here to see if things can be improved.

[Otis]

I've done a few over the years, both 350/4 and 400/4 (re-built one of these last week). 350-4 and 400-4 are identical in terms of the primary chain / sprocket / starter clutch arrangement.
Whilst you can remove the primary shaft from the engine with it in situ, the primary gear, etc, is still "inside" the primary chain itself. Only way to get this out is with the lower crankcase removed - which of course means removing the engine itself.

No real problems (Haynes manual is pretty good for these), other than maybe previous owner bodges / poor maintenance, and the fact that these things are approx. 50 years old.

IF maintained properly, the 400/4 in particular is an exceptional bike. My current hack (only used in the winter these days) now has over 125,000 miles showing - and still on original pistons / rings yet does not burn oil. The cam chain and primary chains in it have now done over 95,000 miles since being replaced - and do not rattle. 350/4 is a slug in comparison and needs to be worked hard to maintain A-road speeds.
Only persistent problem has been oil weeps from the camshaft oil feed through the head gasket (every 25,000 miles or so), due to the use of crap (and expensive!) sleeve type seals around the oil jets. I am trialling a modification here to see if things can be improved.

That's really useful information Chris and I thank you for it. I recently came across a local engine builder (Hammer Engine Solutions) who will do the rebuild for me if I take it to him. He charges £60/hr so any idea how long it might take him? I am tempted to have a go myself but would likely spend weeks and could come across problems. Would you think it's worth having a go myself?

[Oddjob]

I had to buy a bigger pair of circlip pliers to get that out last time I took a 400 apart. My normal SP circlip pliers just didn't have the strength in the handle, it would actually twist with the pressure. You don't want to be in way of it either if it lets go!
As for the cam tensioner horseshoe, I've never seen one that hasn't had some chain damage. The one sold by DSS is an excellent replacement having a proper pivot pin fitted, a shame the guy who makes them in South Africa and who is a member on here is unable to sell them direct due to the postage charges involved.

Having grown up in South Africa in the 1970's I would very much like to know who the SA chap is?

He's called TTR400 and his website is here.

http://www.ttr400.com/

Does great work.

[Otis]

I had to buy a bigger pair of circlip pliers to get that out last time I took a 400 apart. My normal SP circlip pliers just didn't have the strength in the handle, it would actually twist with the pressure. You don't want to be in way of it either if it lets go!
As for the cam tensioner horseshoe, I've never seen one that hasn't had some chain damage. The one sold by DSS is an excellent replacement having a proper pivot pin fitted, a shame the guy who makes them in South Africa and who is a member on here is unable to sell them direct due to the postage charges involved.

Having grown up in South Africa in the 1970's I would very much like to know who the SA chap is?

He's called TTR400 and his website is here.

http://www.ttr400.com/

Does great work.

Wow, thank you for that. I'm sure we will have a few stories to share.
Kind regards
Graham

[exvalvesetdabbler]

On the 400, the engine can be lifted out of the frame by two people once everything has been disconnected, breather cover and sump removed. There's no need to lay the bike on its side. Just tape up the bottom frame tubes if you care about paintwork. A small wooden  box and battons helps to rest it on when it's half out.

Dave.

[K2-K6]

If you're going to do the repair yourself, consider a very thorough clean, upside down on wooden pallet or similar, degreasing with stiff brushes to get into all the details around the crankcase joints etc cleaned of residual dirt/grit that accumulate over time.

You don't want to drop anything into the inverted case when you remove the lower crankcase in getting access to the components. 

They're, all these era four cylinder Honda engine, not difficult to carry out this type of repair, simply diligent dismantle and reassembly procedure in getting to the part you need to replace.

With any parts you need to hand plus joint sealant and any cover gaskets etc, probably within two hours is easily achieved for the repair after engine is out and ready to work on. Certainly less complicated than often imagined.