Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - SumpMagnet

Pages: [1] 2 3
1
Other Bikes / Didn't need a new project...but I got one!
« on: September 22, 2023, 06:11:46 PM »
Been struggling off and on to find time to finish my 750F2 ..... and doing a load of stuff to my daily ride....and then, well..I got made an offer I couldn't refuse.

this is basivcally a family heirloom. My father bought it some 45 years ago, slowly brought it back to standard, then it got mothballed for a bit, partially pulled apart, then sort of left. He was busy renovating other folks bikes, and she got a little neglected. I was asked to give it a new home....and had to say yes.
Comes with some issues, needs cosmetics and most seriously...the distributor had been popping out, which was traced to ovalling of the crankcase opening where it sits. I have a spare set of cases, and a 500 head and barrel ( +20...but needs a rebore) Plus an assortment of other bits and pieces. 2 sets of exhausts, electrical goodies....3 boxes full!

So now I got that to play with as well!

For the record, she's a 1959 Triumph 3TA

The 500 top end is a straight swap, which is why I think Dad bought it. Gives a useful increase in performance.

Paint has a number of issues, but from a distance away...it looks pretty. And it's complete. Nearly.

https://i.imgur.com/hHkzd6K.jpg

2
Misc / Open / Double Take .... its got a WHAT?
« on: April 26, 2023, 07:14:35 PM »
https://www.ebay.co.uk/itm/275817767179

Idly mooching through E-Bay on my lunch break, looking for those bits I just can;t seem to find, and got distracted looking at whats cheap and I ran across this....
did a double take .... spent the rest of my lunch wondering WHY!

3
Misc / Open / Paint Stripper....
« on: April 09, 2023, 06:09:45 PM »
OK .... can anyone give me a source of the mythical 'paint stripper' .....a chemical you used to paint on and it would make the paint fall off.

Not the stuff you can buy these days, that barely softens the stuff..... the real deal Methylene chloride and all!

I have a mudguard I am trying to strip. It's got rust around the edges, and flaked paint...but after a day of stripper soaking, all it has done is take the clear coat off. A second application almost got bits of it down to base coat, but nowhere has it actually got the surface anywhere near metal where paint actually adhered.

Need the good stuff! The stuff you actually NEED to wear gloves for, and cover exposed skin. Not the stuff you could mix with lemonade and still drink without ill effect ( well...not...but its weak as gnats urine!)

4
CB750 / Rubbers between the barrel fins.
« on: October 29, 2022, 02:28:58 PM »
Just been getting my various engine casings etc. painted while the unseasonable warm weather continues.

Had to lever out the rubbers that sit between the fins on my 750F2, which are hard as bullets and not particularly nice. The fins seem to have been drilled to locate these round bungs that spread into the hole to help them stay put.

Are they available? ( I can;t seem to find any, but may not be searching with the right terms.... )
Are they actually doing anything? ( they did cut down ringing vibrations on 2 strokes I have owned, but they seem to have deeper and thinner fins )

5
Misc / Open / Plastigage? and main bearings.
« on: August 11, 2022, 07:47:15 PM »
How exactly does this stuff work?

Was going to reuse the shells on my 750 project until...today. 

Got some time off work so I decided to start cleaning down the crankcases to get them ready for paint. Stripped off the wrappings they were hibernating in...only to see an issue. Where the main bearing shells used to be showing that even dull wear ..I saw one of them had a 'shiny' mark on it. Shiny isn't good. Even worse is when you find the shiny mark is a gouge. It's not wear...something pointed has fallen on the bearing, and dug a chunk out. It;s sharp and stickes up above the worn surface.

That tells me it's scrap.

If I am going to have to replace one....I am assuming I should be replacing the whole lot as a set?

I think I need plastigage to check clearance.... but I have never done anything like this on a plain bearing engine. Don;t have a clue where to start!

6
CB750 / Exhausted....maybe the DOHC world has an answer
« on: July 24, 2022, 11:15:30 AM »
I knew from day 1 that I didn;t want a stock exhaust on my 750 F2 project. It's one thing that I have hardly ever had on bikes that I was riding back in the day, or was that fussed about. Original pipes rotted out, and when that happened the price of new replacements was always far beyond my pocket. So on would go the dodgy 4-1 if I felt flush....or something dodgy and cheap from a breakers if I wasn't.

Now....my bike came with a reasonable front half exhaust, bit rusty, but nothing too serious. There was some rot at the join which I have fixed, but the damn things refuse to come apart so I can finish the job. But even then, its gonna be a hell of a clean up job, and probably a rechrome to make them look presentable. If I can find somewhere willing to do the job on well used pipes.

I have looked to the second hand market. Dear god....do people really pay £400 and up for rusty and battered old exhausts? Everyone wants that for them, but I followed a couple on E-Bay and they don;t sell. Not surprised. The sellers don't seem willing to take low offers either, which is all I would pay for what looks like scrap to me.

I looked for new...and options are limited to 4-1 pipes I don;t really like, or some very overpriced stuff, mostly from the US. Earlier bikes have a flourishing ( and eye watering ) replica market.

But....there seem to be some options available for the DOHC early 4 pots. 79-82. A 4-2 with a pair of shorty mufflers would suit my build just right. But I don't know if they fit, have no way of checking, and really want to avoid having to buy something to find out its wrong. They head/exhaust ports look similar, and the only major issue I can see would be the sump would be different. The pipes may hang a bit low, as they would need clearance for the DOHC deeper sump. But I don;t know if that would cause problems in the corners...or not. I'm hoping someone out there has done it...and can tell me if it is worth the effort.

Meanwhile...I can carry on trying to find a full set of split collars for my exhaust. I have...1 ....where I need 8!

7
Misc / Open / What makes a classic bike tax/MOT exempt?
« on: June 05, 2022, 11:20:33 PM »
Was pondering this the other day, as you do.

If I was to buy a CB750 frame, for example....get it properly UK registered. and then build a bike around it from a more modern vehicle. Lets say, a 900 Hornet or late model CB750 DOHC.

UK registration is based around the frame number from what I recall, so I guess it could legally stay registered with it's 1970's numberplate, and be considered a 1970's vehicle. But as you swap the engine, suspension, wheels, brakes ... does it still get considered as a 1970's vehicle in terms of these things? Is there a point at which your vehicle ceases to be a tax, MOT and emissions exempt vehicle and becomes something else. Or does it just stay as a 'modified' classic vehicle.

I know it would involve an interesting conversation to insure it .... but thats another question.

8
CB750 / need a custom engine mounting bolt...
« on: April 02, 2022, 07:15:36 PM »
Does anyone know where I could get one made?

I am fitting rearsets on my 750F2 project, and the upper rear engine mounting bolt goes through the F2's chunky alloy footrest hangars and through the footrests themselves. The thing is 12mm diameter,  430mm long, with an M12 x1.25 thread at both ends. Well....as I dont have the footrests on this anymore, my bolt is about 30mm longer than it needs to be, and sticks out quite a bit on both sides. Plus, as there is about 20mm of thread each end, I would need to pop in spacers to tighten it up too. Just looks wrong.

I need to have one 30mm shorter.

At a push, I guess I could buy a spare stock bolt and cut it down...but I would also need to buy the right die to cut the thread, as all mine are metric standard...not metric fine. The bolt is also going to be fairly hard steel...so a decent die would be needed to cut hte thread I need before I chop the bolt down. I am not going to damage ANY of hte original parts that are usable, so the bike can be put back to stock ( or as near as it was when I got it ) at any time.

I am reckoning it may be cheaper to just get one made up

9
Misc / Open / carnivorous plants ..... coz folk were asking!
« on: December 07, 2021, 07:13:39 PM »
Great things to keep on a sunny windowsill, fascinating to watch...and a good way of dealing with some of the pesky flying things that get in the house, and can;t get out again!

This is my biggest plant....



It's a venus flytrap, dionaea muscipula to the fancy talkers. This specimen is a 'B52' variant, one of the biggest. A well developed plant can make traps up to 5cm across, thoguh this one mostly has traps 3-4cm across. They are basically green....but have a central part of the trap that goes pinkish....probably to help lure in those flys. In some variants, it can get very pronounced as well. The more sunlight it gets, the redder it goes.

This fellow....



Is a variant that has taken the red almost to purple. It's an 'Akai Ryu' or red dragon variant. Looks spectacular in summer.

I also have a base variant flytrap that has got to be over 10 years old...possibly older. It was the first one I ever got, from a DIY shops garden centre. Usually...these end up dead, either from abuse or poor care. They are also force grown in artificial media...and not with any great care. Mine was lucky, and survived. Its still going strong after being repotted a few times.

The weay these things work is fascinating. On each 'trap' there are 3 trigger hairs each side. If an insect hits one...nothing happens....until the second contact... which causes the trap to snap shut. Not completely shut, but enough to trap prey. Then....as the insect struggles, the hairs are further stimulated, causing the trap to tighten. Eventually, the trap presses together tight enough to form a seal...and the plant starts to secrete digesting fluids to break down the insect and absorb the nutrients. Each trap can trigger a couple of times before the hinge basically wears out. This is how most DIY shop plants die....starved...as the traps are triggered with no food...die...and the plant tries to grow more. They grow in poor soils with little nutrients and need payback for the effort a trap takes to grow.

Care is simple. Stand them in a tray, and let them soak up the water. Use de-ionised water ( mine get rain water) and give them plenty of sun...but not too much heat. Feed them flies. I use an electric zapper to stun prey, as I think live prey is what they want...though to be fair....I open the window and they catch what comes in...and in summer, I let them sit outside. They do a good job feeding themselves.

I also have a sundew or two...

which catches flies by means of sticky sap globules on the leaves. The sap is acidic enough to dissolve the juicy bits of bugs, and the things just land on and can't take off again.

and some pitcher plants....both the upright Sarracenia types, which are basically trumpet shaped death traps for insects, and Nepenthes ...which are the hanging down types. These things catch ground insects that fall into a corrosive swimming pool of digestive juices.

But the flytraps are the active hunters :)


10
Misc / Open / Spares prices????
« on: October 20, 2021, 04:49:50 PM »
As I am looking for a few bits and pieces, I have been keeping an eye, specifically, on 750 F2 parts prices.

Have to say...some of it is absolutely shocking.

Under the seat is a plastic toolbox compartment....DK Spares were selling the bottom half ( minus top) for £49 ...and £25 for the top! A set of exhaust headers, with a socking great hole in one part of the collector with a crack on top....£45  The thing is basically scrap, with heavy rust all over.....£45. £250 for one with a massive patch over the silencer where it's blown out ( where they all go....I have one that did the same.... ) a big dent and other holes. Plus no mounting bracket. They wer eselling a sealed beam headlamp assembly for £60 as non working...the main beam filament has blown. £40 for one footrest.

Now I don;t know if these prices are ever actually obtained, but if they are....my discarded parts pile is worth around £500 in DK prices.  Rear grab rail, seat cowl, footrests, pillion pegs, footrest hangars, toolbox, rear light, rear light bracket, inner mudguard ( plastic), seat trim ....and some very rusty indicators.

This might be genuinely what these things are worth now, but it just seems to be getting a bit 'tasty' in terms of what people think rusty old motorcycle parts are worth. Especially parts that really don't look to me like they are ever going to be useable. Sure, a slightly scabby exhaust can be rechromed....but a pipe that has blown apart and rotted....you can't weld it. You can't rechrome it...its had it

11
Misc / Open / Are fibreglass tanks actually legal?
« on: October 18, 2021, 02:03:51 PM »
Was having this discussion as a follow on to the great E10 debate.

A friend was thinking of buying one for his old school 60's cafe racer, to replace a rather tatty old original one. He has had issues with rust, and sealed it.....but is now worried about E10 eating the liner material. Personally...I think he's bonkers to fit one these days.... but the question I couldn;t find an answer to is whether its actually legal.

There are plastic tanks on bikes, and I have had bikes with them....but fibreglass never seems to do well in a crash. It cracks and shatters rather than denting.
Then, of course, there is the effect of Ethanol on the resin. Unless you seal it...the resin is going to get dissolved.

so. Given the risk of the resin turning to goop in your carbs and the tank leaking..or splitting in a crash and rurning your pride and joy into charcoal.... are they road legal, and how does it go with insurance companies?

12
CB750 / brake lines .... are braided steel worth it here?
« on: August 21, 2021, 02:53:50 PM »
I have had various bikes over the years with stock hoses and with braided steel...another back in the day 'fast lad' upgrade.

I have found some bikes responded well with braided hoses, and others felt wooden as hell and rather horrid. The things usually improved braking ..but a lot of that was down to the fact that they were replacing 15 year old hoses that were past their best.

So, what would be best for a 750F2 ?

My hoses are well shot, and the bike came with US spec high bars, so the front top hose was too long anyway. Rear hose was full of crystalised fluid and corrosion.....and was bin fodder too.
For the sake of safety, I want a full set of new hoses. No point in replacing seals and pistons etc. and NOT doing the hoses.

13
CB750 / Head bearings that actually fit?
« on: July 13, 2021, 10:34:31 AM »
Having moved house, and actually got a GARAGE .... it's time to get my act together and start the rebuild of my long stalled project.

That means getting the forks and wheels on, so I have a complete rolling chassis so I can dry-build the big bits. I have already bought one head bearing kit...only to find it simply did not fit.

The bearings were the correct diameter for the stem, top and bottom...and hte bearing cups fitted the headstock just fine. Trouble was, with everything properly home....the stem would not go through far enough to actually do more than just catch the threads on the stem nut. No way was I going to try and progress that.... And whilst I had fitted the seal/washer..it was sitting over the stepped lower bearing and not stopping the lower from sitting tight to the lower yoke. Besides...to actually fit the upper nut right onto the thread, I was going to need to find about 10mm .....and thats not a bearing seating issue. After I removed the parts....I tried building up the stace various ways, and couldn't see a solution. So scratch that.

so my dilemma is simple.... .I need to buy another set of bearings...but I want to get one that fits, not one that will give me the same run around and hassle I have already had.
I prefer taper roller bearings..... but as an absolute last resort.... I could pay £66 and get an original set of cup/cone bearings and balls from Silvers. It's twice the price of most of the taper roller sets, but I guess it guarantees a fit.

Are there other reliable options for my F2 that will fit?

14
Misc / Open / Tyre kickers......
« on: May 24, 2021, 05:11:53 PM »
I had forgotten how REALLY annoying these folks can be. Especially now they can do it online without having to even get out their front door!

I have a bike I don;t use much anymore, so I figured...as I am trying to move house...that now would be a good time to move it on so I don;t have to pay to get it transported. I took loads of photos, did a bit of research to see what others of similar age and condition, carefully chose a price that was at the lower end of the scale, as...while it is in excellent condition and has been well looked after all the while I have owned it, it's on SORN and there are a few minor issues. All of which were carefully listed in the advert and visible in the pictures. I even included pics of the tyres, as it had recently had a new pair fitted before it was laid up.

"what's the tyre tread like mate?" .... like in the pictures of the tyre tread....

"will you take 20% less than the advert price to sell it now" ... no

"Is the paint faded and rubbed on the fuel tank?" ....no 

"is the paint faded eslsewhere if not on the tank?" ...its all in the description...

"I'd need to have some money off to pay to have it couriered" ....you what????

"you said it needed a battery...I would need some money off for that" ....no...thats already been accounted for and stated

"Will you take 25% less than the price if I pay now...it's all the money I have" ...well, then you can;t afford it can you

"Will you take 25% less than the price if I pay now...I'm a bike dealer" thats nice for you. But not a reason I should give you a bargain

Now....it's not that I don;t mind a haggler, but NOT ONE of these folks has come to look at the bike, heard it start, or given one good reason why I should knock money off. Is it just assumed I have listed it for £500 more than it's worth and there is some unwritten agreement that an AUCTION site is where you start high and work down? Now I have tried to get money off vehicles before, but at leasty I went to the trouble of going round, standing in front of it, and finding faults and issues the seller had not mentioned and using that to bargain with.

Give it a minute, and my inbox will ping with a fresh message asking me to give the bike away for peanuts.

15
CB750 / Exhausted by exhaust
« on: December 13, 2020, 04:34:39 PM »
House move plans dragging, so while I am stumped for big stuff, I thought I would go back to a few of those jobs I put on the back burner. Like the exhaust on My F2.

Half of it was scrap. I had some corrosion around hte collector, but the rear pipe was total scrap. Huge hole blown out just behind where it joined, and paper thin metal all along the underside that I could push around while it made crunchy sounds. Baffles were shot too, and not really attached. The front section, however, is actually surprisingly good.

Quite a bit of surface rust on the collector...which I have been cleaning off...but it is really pretty solid. Will need some welding where the pipe went into the joint gasket, as moisture clearly got trapped and rotted out the steel...but only where the gasket sat. Should be an easy job to weld in some fresh steel there...

The pipes themselves have some surface spotting, but no dents and just a couple of scratches/scrapes...none of which are deep. Should clean up...then I guess it sould be possible to re-chrome.

BUT....here's the thing.

I cannot get the 2 removable header pipes to shift. 2 are welded into the collector...but 2 are seperate. The clamps came off really nicely with a squirt of WD40, but they were not rusted up.
If I am going to get them refinished....the pipes have got to come apart? I can see a gasket in there ( or what looks like one) but if it's fossilized like the other one....it's going to be a pain to get loose. The one I did remove was easy ( relatively) as the metal around it was scrap and I could cut it away then break off the gasket bit by bit. Cant do that here. Heat also seems to do nothing, as the gasket was designed to cope with high temps, and the metals are exapnding at the same rate.

Any hints or tips????

Pages: [1] 2 3
SimplePortal 2.3.5 © 2008-2012, SimplePortal