Roadster/Interstate/Thruxton R tank (2020)

I guess if this tank ever gets dented it will become a painted alloy tank.
The weight savings steel to alloy on the tank is quite a bit-
14.5 lbs. for the 25l Interstate tank and 7.2 lbs for this 22l tank.
Glen
If I could do what you are doing, I wouldn't care if those weights were reversed just to have the pleasure of knowing I had made them.
 
I'm pretty used to living with the alloy as I made the Egli tank 9 years ago now. No dents in that one. If I drop the bike then the alloy tank will likely get a bigger dent than steel, but either way you have a big problem.
Speaking of which, I recall that it was Ross Thompson who finally properly repaired my friend's original Series A Vincent Rapide tank.
The tank was full of dents filled with lead and Bondo. It went to a local metal shaping expert who unsoldered the bottom and worked the dents out. He spent a lot of hours doing that and soldering it back together. Cost was about $3,000. Then my friend put fuel in it. It had about 9 leaks.
The metal shaper said, not my fault, I'm a metal shaping expert, not a soldering expert.
So a soldering expert was hired to fix the leaks $1000 later it was leakproof. The metalshaping expert's job had improved the surface of the tank a lot, but it still looked pretty rough to me.
Next it went to a very high end painter who was known for doing expensive custom Harley paint jobs. He made a nice job of it,cost about $2,000
Then my friend installed it and found that, after being filled with fuel for awhile, still had a weep. He tried fixing it and ended up overpressurizing it which turned it into a very large strange looking tank.
At this point it was shipped to Ross Thompson Metal Finishing.
We don't know how did it, but with great skill and many careful hours spent, he took it all apart, reshaped it to original shape and put it back together such that it was sealed. Every surface was perfect this time, no "patina"
I believe that ordeal cost about $3,000.
Now it went back to the fancy painter for another $2,000 paint job.
That's how to spend $11,000 fixing a motorcycle fuel tank.
A steel one at that!

Glen
 
It seemed like a good time to make the rear mudguard, since I'm in that mode.
I hadn't figured out quite what to do with the back end, so the MK3 mudguard was removed and propped into place for a look


This doesn't look quite right.
I don't care for the level hoop and the upward curving Thruxton cowl
Things also look off from behind.
 
I'm going to make a plate holder that will attach to the hoop and forgo the rear mudguard for now. More weight lost, if it works.
It just looked odd with the mudguard in there, especially with the long level hoop.
I have a short section of very wide rear mudguard left over from the Egli project. I made that mudguard quite long then trimmed it.
The offcut fits perfectly in front of the rear wheel to fill that big opening. That will keep crud from flying forward onto the engine.

Glen
 
Here's that piece. I spent a crazy amount of time pounding on that 8" wide mudguard . As the width increases so does the difficulty in creating the radius. With a 4" mudguard pounding the crown in creates lots of wheel curvature. 5" not so much. And 8" wide barely curves at all. It was such a battle to get the 8" done that I couldn't throw the offcut away.
Good thing, after 9 years later it's needed.
 
Good job with the hacksawing there Glen, that rear loop let’s down many a special to my eyes, and certainly wudda let yours down.
 
Thanks Nigel, I know you have a good eye for such things.
I'm still not 100% sure on how this bike will look or handle. With old meets new it can always end badly!
The aim is for a purpose built look.
Trying to keep the $budget low but the free labour budget is quite generous.
Also managing to use up some of the parts that have been kicking around the shop for years.
Glen
 
I'm going to make a plate holder that will attach to the hoop and forgo the rear mudguard for now. More weight lost, if it works.
It just looked odd with the mudguard in there, especially with the long level hoop.
I have a short section of very wide rear mudguard left over from the Egli project. I made that mudguard quite long then trimmed it.
The offcut fits perfectly in front of the rear wheel to fill that big opening. That will keep crud from flying forward onto the engine.

Glen
Are you going to put a plate in under there for a battery and/or storage?
 
Yes, there should be a fair bit of storage space there.
I've ordered the Triumph latch set and cable. That was only $30 and will allow for a quick detach seat. The other part of the Triumph seat latch system is a lockset that uses the ignition key to operate the latch. It's a very neat setup, but the key is $300 and the lockset is $200, so scratch that.
With just the latch and cable, a small lever can be mounted somewhere to operate the latch.
That way the seat and cowl will be instant off and on for access to that storage area.

Glen
 
I separated the cowl from the seat pan.
The cowl is fixed to the frame, and the actual seat simply 'clicks' in place.
this way I can open it even with luggage on the rack.
I keep rain gear in there, and cram dirty laundry in the back when traveling.
The rear loop is also shortened 5 cm.

Roadster/Interstate/Thruxton R tank (2020)
 
There isn't any storage space in this cowl I'm afraid. It's just a cover that slips over upholstered seat material. It's a bit of a waste as I was able to fit the battery and most of the electrics under the large Egli cowl. I made that one just large enough to fit around all of the electrical items.

This Triumph cowl is very small, so its not a huge loss.
There is going to be some useful space below and it will be quick access.
The luggage is all going into the quick attach Triumph panniers on the sides.
I've been using these for a few years now on the Thruxton and really like the simplicity as well as appearance. One other member fitted them to his Commando, I believe it worked out well.

Glen
 
The luggage is all going into the quick attach Triumph panniers on the sides.
I've been using these for a few years now on the Thruxton and really like the simplicity as well as appearance. One other member fitted them to his Commando, I believe it worked out well.

Glen
Yup.

 
Gortnipper I was just about to post that photo, you beat me to it.
Looks nice on there. Sweet looking bike helps!


Glen
 
Yes, there should be a fair bit of storage space there.
I've ordered the Triumph latch set and cable. That was only $30 and will allow for a quick detach seat. The other part of the Triumph seat latch system is a lockset that uses the ignition key to operate the latch. It's a very neat setup, but the key is $300 and the lockset is $200, so scratch that.
With just the latch and cable, a small lever can be mounted somewhere to operate the latch.
That way the seat and cowl will be instant off and on for access to that storage area.

Glen
If the seat lock is the same as Japanese bikes use then instead of the remote cable operated key lock for the seat I have found a piece of 1.6 stainless Tig wire formed into a loop works well on these mechanisms
Just reach under the seat and pull the loop
 
After a lapse I'm back working on the bike. This RH10 head was for sale for months in the forum classified section, $400, no takers. Because there seemed no other interest, I tried $350, but the seller held firm.
So $400 it was and what a nice head it is!
I assumed it would need the works as far as rebuilding. Going through it today, it didn't need anything other than general cleaning and lapping the valves.
Here's what I found-
Norman White says replace the valves if stem wear is .0015 or greater.
These valves measured .0002 of wear, negligible.
I don't really have a good way of measuring the guides, however Jim Comstock suggested that wobble with the valve just off the seat should be less than .5 mm.
He also mentioned that he has seen running bikes with 3 mm slop.
I love it when a professional gives you a guide number. Those numbers are golden and I try to commit them to memory.
So I set the dial indicator up and found .005", about .12mm, so negligible wear there as well. Any tighter than this and one might expect a valve to hang up. Another bonus, these are the nice,high quality Colsibro guides.
The rockers look and feel good as well, nothing needed there.
What it did need was a good scraping of the cc as there was about 1/8" of carbon/slate bonded onto everything.
The plastic scraper had no effect, so I made a scraper from some copper water pipe.
That worked well. The copper is softer than the Al of the head, so it doesn't do damage.

If the fellow who sold the head to me reads this, I have a message- Please forgive me for trying to beat the price down!

 
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Am I leaving some 3-5 k rpm performance untapped with a stock RH10 on a 920?
Regardless, that will be the head for now. The border is almost shut for shipping and Jim Comstock is about the only guy I would trust on porting. I expect he might say, for a torquester, don't bother if running stock cam, carbs and slightly above stock Cr.
But it is a 920 so perhaps it might benefit from bigger valves and ports. I might do this in the future if the 3-5k power can stay the same.


Glen
 
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