Inlet Manifold studs - modify?

[Orcade-Ian]

Hi folks,
Been mulling over the method of carb fitment on this 550 - the 350 and 400's are tight for space but I think the 550 is even worse.  I have new manifold and airbox rubbers but don't like the idea of distorting them considerably to fight the bank back in.  Yes, the air filter box is free, giving a bit more wiggle room.  I know one or two folk have replaced the studs with bolts but that would be too visible.  I'm considering removing the studs and silver soldering the nuts on and then re-plating them, so that they look right but act like bolts.  I would probably remove about 1mm from the head end of the studs so there was no fear of them binding up.  I would always prefer stud fixing so as not to wear the threads in the head but they don't come on and off that regularly (he said!)
Any thoughts?

Ian

[Trigger]

Seems a lot of work for something that can be fitted in the time it take to make a cuppa 

I must of fitted hundreds of carbs over the years. To make life easier :
Fit the clamps after you have the manifold rubbers on. Put a smear of red rubber grease , on the air box to carb rubbers , drop the manifold rubbers in boiling water, take them out after a couple of minutes, (start on number 2&3 ) wipe dry, a spray of back to black silicone and they fall on.
Replace the two m6 bolts in the air box mounts and feed the clamps round the rubbers, place a smear of copper grease on the JIS screws and tighten up 

Always harder with old hard rubbers 

[Oddjob]

I've found that the easiest way to get carbs on and off is to drop the engine forward, that's assuming you've got the engine loose in the frame. So after fitting the engine just fit the back lower bolt and the back upper bolt, fit some frame protection around the frame tubes, like copper pipe insulation for instance or rags etc. Fit a small jack under the engine just to take the weight, remove the upper rear bolt and the engine will tilt forward, fit the carbs now and you'll find they go in easily and with all the rubbers in place. You can also remove the airbox mounting bolts and pull that back a little if you want some extra room.

Don't get the comment about bolts being too visible, I intend to replace my studs with bolts this time round, I'll be using the later 8mm headed bolts that Honda are still using. TBH they should be less obvious than the larger 10mm nuts it currently uses. Without the studs the carbs should slide in no problem. It's whether the bolts are easy to get at that may be a problem.

[Orcade-Ian]

Thanks Graham,
I might give that method of yours a try first, it obviously works for you.  The new rubbers are DS aftermarket ones, I hope that doesn't make it more difficult.  Ken, I was meaning the bolt 'bodge' would be obvious - visible is probably not the right word.  I was attempting to keep it looking standard and not modified - yeah, I should get out more!

Ian

[McCabe-Thiele (Ted)]

On my 400 I found it pretty easy to fit the carbs back in place when the rear wheel, mudguard & battery box were not in place working backwards from the carbs  it was easy to fit things without the struggle of a tight gap or distortion. The battery box on the 400 comes out easily with the plastic section of the rear mudguard out.

I don't know if that is the same amount of time involved as tipping the engine or more.

[Oddjob]

IMO Ian far too much emphasis is placed on not modified these days. There isn’t a single bike on the road of our age that hasn’t been modified in some way. Be that by fitting LED bulbs or by fitting sintered pads for instance.

If the mod makes the bike better or easier to work on why let a really small thing like “people may spot it” deter you. Getting carbs in on the 500/550 can be a nightmare of a job, with the advent of modern fuels etc the chances of leakage greatly increases,  meaning you may have to remove them in order to fix little problems, anything which helps you do that has to be a good thing.

[Orcade-Ian]

Ted, having done quite a few 400's and a couple of 350's which are pretty much identical - fitting space wise, the 550 is a whole lot tighter.  I obviously respect Graham's view - he and many others have done so many, it becomes second nature but as a 550 Virgin, I just wanted to share my thoughts on the process.
Ken, I'm certainly not averse to modifying something to make even a small aspect better and will almost certainly do this stud/bolt mod.  When I was serving my apprenticeship an older, wiser guy said to me 'When working on any machinery or equipment, always make it easier for the next guy to do his job - it might be you!' 

Ian

[AshimotoK0]

Seeing as you can silver solder and BZP  at home Ian,not a long job to do and so  it sounded like a good idea to me ... easier to fit and looks original.

[McCabe-Thiele (Ted)]

Ted, having done quite a few 400's and a couple of 350's which are pretty much identical - fitting space wise, the 550 is a whole lot tighter.  I obviously respect Graham's view - he and many others have done so many, it becomes second nature but as a 550 Virgin, I just wanted to share my thoughts on the process.
Ken, I'm certainly not averse to modifying something to make even a small aspect better and will almost certainly do this stud/bolt mod.  When I was serving my apprenticeship an older, wiser guy said to me 'When working on any machinery or equipment, always make it easier for the next guy to do his job - it might be you!' 

Ian

Ian I was just sharing my limited  experience on a single 400 that I took the carbs off a few times - having never tilted an engine like Graham I have no idea how easy or difficult that might be I just have this vision that it might involve removing the silencer that might be rusted on etc.

I would never presume to know better than Graham, Bryan Ken or anyone else here for that matter.

Just shared my method fwiw not trying to out do - anyone sorry if that is how I came across.

[Orcade-Ian]

Thanks Ash,
Head - nail, nail - head! 

Ian

[Orcade-Ian]

Ted,
No offence my friend - this forum is all about learning from each other and sharing good and bad.  I'm only doing the necessary to this 'James 550'. (did they ever make a 550? My Dad had a 98cc) I'm reluctant to remove the exhaust and other bits at this stage just to make refitting the carbs easier!
I've also got a set of the correct 069 carbs in the pipeline to do the 'bling-over'  on, so these will have to come out again - so I will be that 'next guy'.  Although I will leave the air plenum and filter box off just to run it in the workshop.

Ian

[K2-K6]

All good methods and experience to draw from there.

On topic of original posting, I can't see any particular problem associated with going that way. Unsure about rating silver solder but easily check with a sample and tourqe wrench to assess if you feel it has enough security. Obviously if it comes loose in this scenario it particularly low risk anyway.

Understand about balance of thread use if they were to be taken off frequently, but hopefully with good recommissioned set that would be avoided.
On that axis though, you could turn a very simple venturi device (or make one from plastic plumbing fittings) to fix engine side of carb body, then using compressed air to draw vacuum, test the jet circuits to ensure flow from idle, main etc without having to run them to find out if they are impaired.
Sight tube on float bowl and you could judge level drop from single fill to give idea of flow.  Or clear plastic connection to carb and shine a torch through while running to see fuel atomisation.

[Bryanj]

Only problem i can think of is bloody O rings falling out! Evostick anybody?

[deltarider]

I've learned to do all carb maintenance with carbs in situ. I can do it blindfolded. Undo the floatbowls is all what is needed. It helps to know what's in there. When you're at it, replace those 16 crossheads by allen bolts.

[Oddjob]

I seem to recall the manifolds have small restrictions in the groove which grip the o-ring Bryan so they don't come out. Could be wrong but for some reason it sounds right.

I'll try the method and report back on whether it works or not, when I eventually build this bike that is.