500 K cafe racer conversion - build thread

[Tomb]

Mathew is spot on to point out that care must be taken using stainless bolts. A2 316 stainless is Ok for engine covers but A4 should be used if replacing 8.8 tensile steel bolts. I've seen lads with shaft drive bikes (XS1100 to be specific) change out the bevel drive 12.9 tensile bolts for stainless, not good!!!

Can I also say that the application, as in how the bolts are used matters, which leads to disc bolts, coz disc bolts are in shear stress they ain't as critcal as bevel drive end caps which are in tensile stress, the disc bolts would have to be guillotined by the disc and ali hub to break and this wouldn't happen before your tyre would break grip, by a looooooooooooooong way.

I have A2 stainless M8 button head screws holding my discs on my XS1100 wheel (avatar bike) with different twin piston calipers fitted without any problems.

Another one to watch for is using stainless nuts and bolts, try to use A2 bolts with A4 nuts to avoid galling and use copperslip. Similar stainless fasteners will gall very easily. Clicky

Tom (time served Toolmaker for 18 years, now working as Mech Fitter in pharmaceutical industry, looooots of stainless )

[Ewan 500 K1]

Be carefull of using stainless for high stress or mission critiacl areas like brakes, it's not nessisarily that strong and I'd be after high tensile steel  or getting bolts from someone who sells parts specifically for this job. Mot stainless is A2 grade and not up to the job for disk holding. Phill Denton engineering are the only firm I can think of who I'd go to for shiny bolts for this job. That said I don't do shiny

cheers for the heads up on that one ... I had it the the back of my mind that normal stainless bolts werent the ones for the job. Tried Phil D a while ago I think , but they dont have the neccsary bolt sizes as stock, would need to do a one off.  Anyway, got a hold off 6 GL1000 disc bolts (112mm long)  from DSS the other day... well  pricey at £22 inc vat and delivery. Hoping they'll do the job. I was going to order new nuts to fit as well, but fell over at the price of those --- £3.25 each +VAT & delivery

just opened my DSS parcel, they only had 4 GL1000 disc bolts in stock.... anyone could a couple (112mm long ), part no. 90122-371-000 ?

sorted, manged to source 6 decent 2nd hand ones, with nuts from this guy in Glasgow: http://www.wingovations.com/

[K2-K6]

Well explained Tomb and valid knowledge for anyone modifying stuff.

I look at some special built bikes and wince at some of the load paths created.

Most high stress stuff makes use of rolled threads as compared to cut stuff as well, many don't take this into account either.

[Ewan 500 K1]

It's been a wee while ....... drilled the two brake discs today. Next up is fitting the double calipers

laterz ...See my seperate post at http://www.sohc.co.uk/index.php?topic=5571.msg27566#msg27566 for the pain and agony of setting up my dual discs

[Ewan 500 K1]

It's been a wee while ....... drilled the two brake discs today. Next up is fitting the double calipers

  Here's what I needed to do it:

1. Roll of wall lining paper (£2.99) for drawing templates on (one tempate need for left hand disc and one for the right hand side one)
2. Prototractor (99p) , compass (99p), 12 inch rule & pencil for drawing out the templates
3. bit of parcel tape to stick the templates on the reverse side of the discs.
4. Centre punch to mark the discs for drilling before removing the temapltes
5. On single 8mm 5% cobalt drill for all 144 holes. (£4.85). One 12.4mm countersink bit (£9.99)
6. Bottle of cutting fluid (£8.99)
7. 2nd hand pillar drill picked up for £30 at a car boot sale

What I did:

1. put the lining paper over the disc and used a pencil to mark the circumference
2. found the centre of the circle on the paper using the compass.
3. marked out 24 sudivisions of the circle
4. Used the compass to scribe arcs and circles on the template to get the hole positions
5. Stuck the template on the reverse side of the disc using parcel tape
6. Used a centre punch to mark the positions of the holes through the paper onto the disc
7. Took the templates off the discs
7. Used a single 8mm 5% cobalt drill to drill all 144 holes in both discs. Pillar drill set at lowest speed (540rpm) and used plenty cutting fluid, making a single pass for each hole using even and constant pressure (ie no reversing back out part way through)... if its going right you get lovely spirals of swarf coming of, as in pic below
8. Gave each hole a light countersink on each side.
9. Job done.

laterz ...See my seperate post at http://www.sohc.co.uk/index.php?topic=5571.msg27566#msg27566 for the pain and agony of setting up my dual discs

[Ewan 500 K1]

ooooooh, I'm so pleased with my dual discs and shiny new wheel
See my seperate post at http://www.sohc.co.uk/index.php?topic=5571.msg27566#msg27566 for the pain and agony of setting up my dual discs

[Tomb]

ooooooh, I'm so pleased with my dual discs and shiny new wheel

My missus thinks I'm a sad git getting all excited over shiny new bits for my bikes

Looks well Ewan

[Ewan 500 K1]

could be worse Tomb, you could could be peeing yer pants over a new microwave 

[Ewan 500 K1]

Bit the bullet last night ... chopped the rear end of the frame and cut off the side panel and battery tray mountings fro the frame mid section.....it's no return now.  Now need to weld the hoop on, make a flat plate to go on top of the hoop and cut out the rear section of the seat base to make space for the battery and electrics under the seat hump.

[Ewan 500 K1]

This will be a year round road going bike, so I need a rear mudguard to stop all the road crap from firing strtaight at my air intake. Bought a 6 inch steel universal job  to cut and fit .... dont like it now, it's tooo wide and ugly. See photo 1, the blue cloth covers the part I had intended to chop off. Second photo shows and alternative solution using the chrome part of the stock rear mudguard. This would need a bit of cutting & modification too. Its not much prettier that the 6 inch steel job (photo 2). Plan C is to buy a 5 inch universal stainless mudguard and cut it.  (later ... plan C was the end result.. see phots in later posts)

[Ewan 500 K1]

I need a rear light.  Originally I was going to build one into the back of the seat unit.  Now I quite fancy putting a LED combination rear light/brake light/ indicator strip onto the rear of the hoop under the seat. So I'm now looking  looking for a flexible LED combo strip ... anyone got any info on UK suppliers ? , preferbaly a plug and play unit that is 12v ready and dosent need any additional electrical fittings.   OR .... plan C is to cut out a section of the hoop, fit lights inside the hoop and then find some sort of sultion to make a lens to replace the cut out section of the hoop... probably a bit ambitious for me, but if anyone has ideas on how that could be acheived, I'd be keen to hear.  Photo of rear end and side view of the bike as it is this morning attached

[Ewan 500 K1]

or maybe something like this mock up....  (laterz .. found something that will do as the mock up pictures show.. ..ending up getting an Z Flex LED flexible array from radiantz  in USA, which took like months to arrive because of a #@%$ up as UK customs , cost a fortune after shipping charges, cuty and some obscure cahreg from shippers to deal with custom, see picture below.. its like that without the indicator ends. Also got a wee bit of circuit from radiantz so that it is a  combined raer light / barke light   see http://www.radiantz.com/index1.html?c6.html&1. God knows if its legal. If push comes to shove and its not leagal I'll put something esle on it for its MOT)

[Ewan 500 K1]

Rear frame hoop ands battery/electrics tray welded up, with gussets behind top shock mountings to mount  indicators on

[Ewan 500 K1]

took the head off to polish it and noticed one of the bolts was snapped, sheared of flush at barrell surface , so barrells had to come off to weld a nut to the broken stud , so good time to paint the engine . Broke a bloody piston ring reassembling the engine = £80 for 4 new ring sets, new gasket set = £40 = £120 for the sake of a broken bloody bolt (dont tell the wife) Good news was that I dropped a bit of the piston ring down the barrell into the crank case but managed to fish it back out with a telescopic magnet thingy , #@%$ was I happy that I didnt have to split the crankacse to fin it  .

Engine all polished an painted and now back in the bike ready to start a complete rewire job. Its 40 years to the day come Jan 1st next year since the bike was registered, so thats become the target date for completion of the cafe racer conversion / restoration. Still to do : rewire, powder coat frame, refine dual disc set up, find some rear sets, rechrome the cut down front and rear mudguards.

Got the engine back in the frame today and put togeather a mock up of the end result. Keeping the old tank the way it is for a bit of patina

[Ewan 500 K1]

ordered a set of avon road runners (120/90 rear and 100/90 front) for the shiney new rims today , some tarozzi rearests to hang off the passenger footpegs, all the wiring bits and pieces and a motobatt sealed unit battery. Was going to get a new camchain tensioner, chain and sprocket ... but the wallet cannae stretch to 220 euros that CMSNL want right now