Author Topic: Dual disc question, K1 with lesters. (Read 2763 times)

jaguar · « **on:** May 14, 2011, 07:53:48 PM »

I know that there are a million threads on dual disk set ups but i still dont understand whats going on with my parts.

I have a set of lesters that i believe were on a latter 750 and im looking to get them to work on my K1.
these are the parts that came out with the speedo

reason that i think they came off a later one is the difference between what came with the lesters and what came off my K1

the one that came with the lesters is cracked....
and the K1 one is "thicker"....

well after looking at the parts i feel that they are not the best way to make the speedo work.
So im really looking for some help as to how to make this all work in the right way.
I would like to use the K1 drive but i assume that means grinding something so im not really sure how i feel

what would the proper way be to drive the speedo?
thanks SOOOooo much for any help

jaguar · « **Reply #1 on:** May 14, 2011, 08:43:22 PM »

there is a nice lip for the speedo drive to sit in

seems to have been ground down to fit.
its not perfect and needs a little adjustment but should do the job

but then there is this piece that the bolts go through.
the opening interferes with the drive housing and i cant figure out of this ever worked on a bike....

using the K1 housing might be harder as it is a VERY tight fit with the bolts

and i would need to figure some other way of anchoring the speedo drive

since im using lesters i dont have the same kind of hub casting as stock.
ive seen some very cleaver ideas when using the stock hubs

so the basic idea is to get the drive to turn with the wheel right? kinda by any means?
right now i cant get everything to move when i tighten everything down due to interference with the parts that i have....

scottly · « **Reply #2 on:** May 14, 2011, 09:14:25 PM »

I went the easy route: NO speedo.

Rookster · « **Reply #3 on:** May 14, 2011, 09:39:18 PM »

Hi Jaguar,
You're probably sick of me replying but I have the same parts; K1 and Lester and I am doing the same thing as you. From where you are now you have 2 options:

Option 1: Cut the tab off speedo drive plate so it will fit inside the disk and drill a small hole through it and into the hub. Get a small dowel and stake the drive plate in place (you could also use a small countersunk screw). The speedo drive gearbox, axle and fork legs will hold everything together (use the K1 speedo gearbox and ditch the other one).

Option 2: Get the back of the disk machined so the drive plate fits tight against the hub and the disk holds it in place. Again use the K1 speedo gearbox and get rid of the other one.

You have to get the drive plate up tight against the hub or else the entire assembly won't fit between the fork legs. The fork legs will hold everything together so the drive plate doesn't nessesarily need to be bolted to the hub but it has to spin with the hub. Either method will work.

Scott

jaguar · « **Reply #4 on:** May 14, 2011, 10:17:00 PM »

no never sick of helpful people

Ill sit down this weekend and try and figure the best way to make the drive spin with the wheel. that doesnt seem that hard.

guess the question now is
why is the K1 housing so much "thicker" then the other one? im not sure that it will fit between the forks unless i grind it down a bit.
ill mock it up and post pics

jaguar · « **Reply #5 on:** May 15, 2011, 02:47:25 PM »

i like the idea of the dowel
how big of a dowel do you think it would take?
im alittle scared of drilling into the lesters
how would the speedo have been driven normally with these wheels?

this is what its like with the K1 housing

and with the other housing.

make a big difference
not sure why they are so different

Oddjob · « **Reply #6 on:** May 15, 2011, 02:55:37 PM »

I've done the exact same mod on my lesters. I used the dowel/rivet method. Cut off the flange from the speedo drive plate. Ensure the plate is flat at the back by using a sheet of glass and some grinding paste. Drill 2 holes in the plate at 180 degrees to each other. Use a drill the correct size for the rivet, I used the steering lock rivet off a Yamaha RD400, they are spiralled threaded and grip as they are hammered in, it's not moved in 30 years since I did this. Fit plate into speedo housing and thread the spindle through it, fit to wheel, carefully hold the plate against the wheel and without moving it remove the speedo housing and spindle. Mark the holes against the wheel flange, remove plate and drill a hole slightly smaller than the rivet, tap rivet in place and jobs done. Don't use the retainer plate as it's no longer needed.

Forgot to add, make sure the modified speedo plate will fit down the centre of the disc, if it doesn't file it down until it does.

Oddjob · « **Reply #7 on:** May 15, 2011, 03:19:45 PM »

Just in case you need them the part number for the rivet is 90269-04003-00
A quick search of the web using that number should show you where to buy them and if there's anyone local to you with them in stock.

jaguar · « **Reply #8 on:** May 19, 2011, 02:15:04 PM »

ok so now i think i have solved my speedo issue..

no on to the disc offset issues.....

seems that one side of the wheel is spaced out more then the other.
both of the discs that i have are the same offset so this is causing one disk to be about 1/4in further out then the other.
the speedo one being closer to the hub

is this normal?

jaguar · « **Reply #9 on:** May 19, 2011, 02:47:42 PM »

what gives with the rotor?

Don R · « **Reply #10 on:** May 19, 2011, 08:15:52 PM »

I used a couple roll pins on my speedo drive on my K0 with a Lester, I would have a look at the new machined drive hub advertised in the parts section if I were to do it again.

jaguar · « **Reply #11 on:** May 19, 2011, 08:48:55 PM »

did you have issues with the rotor offset?

Oddjob · « **Reply #12 on:** May 20, 2011, 03:35:12 PM »

The caliper on the R/H for slider needs to be spaced out. You'll find that the mudguard stay unlike the L/H slider goes behind the caliper top mount, this helps a little but it's still not enough. I can't remember off hand what size spacers you need but I did it by loosely fitting the caliper, leave the bolts very loose to allow the caliper to move outward. Fit a new set of pads and align the rear pad onto the disc, this should move the caliper along the bolts, you'll get an idea then what thickness you need, I seem to recall the pin spacer is around 2mm thick, unsure on top ones as I welded mine to the mudguard stay to stop any chance of losing them. Make sure you get the caliper parallel to the disc when doing this BTW.

jaguar · « **Reply #13 on:** May 20, 2011, 04:17:53 PM »

Quote from: Oddjob on May 20, 2011, 03:35:12 PM

The caliper on the R/H for slider needs to be spaced out. You'll find that the mudguard stay unlike the L/H slider goes behind the caliper top mount, this helps a little but it's still not enough. I can't remember off hand what size spacers you need but I did it by loosely fitting the caliper, leave the bolts very loose to allow the caliper to move outward. Fit a new set of pads and align the rear pad onto the disc, this should move the caliper along the bolts, you'll get an idea then what thickness you need, I seem to recall the pin spacer is around 2mm thick, unsure on top ones as I welded mine to the mudguard stay to stop any chance of losing them. Make sure you get the caliper parallel to the disc when doing this BTW.

right now im still stuck at the disk to fork leg offset.
the rotor that looks closer is the left side and seems to be right. but the right side rotor seems to need to be shimmed out a bit to match the left side.
guess the question is, do both the rotors need to be the same offset from the legs? i would think that they do.

scottly · « **Reply #14 on:** May 20, 2011, 07:41:47 PM »

Quote from: jaguar on May 20, 2011, 04:17:53 PM

right now im still stuck at the disk to fork leg offset.
the rotor that looks closer is the left side and seems to be right. but the right side rotor seems to need to be shimmed out a bit to match the left side.
guess the question is, do both the rotors need to be the same offset from the legs? i would think that they do.

The rotors will work with the different offset, provided the caliper is aligned parallel to the disc. I didn't like the asymmetrical look, so I ended up shimming the right rotor out .150". (Morris wheel)

jaguar · « **Reply #15 on:** May 20, 2011, 08:18:36 PM »

what did you use to shim the rotor
the asymmetrical look doesnt sit well with me either.

im worried that shimming the rotor will be hard to do and keep the balance

scottly · « **Reply #16 on:** May 20, 2011, 08:54:16 PM »

I made a spacer with a flange, as I used Yamaha discs that had a larger center hole than the Honda, plus they had less offset to begin with. The hard part was making sure the spacers were the same thickness all over, so the discs wouldn't wobble.

jaguar · « **Reply #17 on:** May 20, 2011, 09:55:18 PM »

guess im going to have to find someone that can make me one of those....

Oddjob · « **Reply #18 on:** May 21, 2011, 11:12:31 AM »

Not 100% sure shimming the disc out will work. IIRC the speedo drive is already VERY close to the disc, shimming the disc out would cause it to hit the speedo drive I think. TBH you can't tell the disc is farther out on the O/S unless your looking for it.

jaguar · « **Reply #19 on:** May 21, 2011, 11:22:57 AM »

its not the speedo housing to dics clearance thats the issue for shimming. its the fact that the bolts that hold the discs together will hit where the cable attaches to the housing.....lame

does this issue not come up when dealing with a factory wheel?
so does it just come down to looks or will the off set in some way affect the handling under braking? i guess it wouldnt as the stock there is only one disc

jaguar · « **Reply #20 on:** May 22, 2011, 08:39:54 AM »

http://forums.sohc4.net/index.php?topic=53532.50

found this, after reading it though it seems that the person that shimmed the disc was not running a speedo housing.
I thought that shimming the rotor would be the answer but after measuring better i dont think it will.

If i shim the disc out on the "odd" rotor to match the "normal" rotor then the bot heads will hit the drive. from what ive read this can be solved by using a lower profile bolt or the ones from a GL. I looked around my stores for parts and dont seem to have any "in stock". but after looking a bit more it seems that after the oddjob you are right, where the cable goes into the housing will touch the disc, might be able to JUST clear it but it looks like it would be almost impossible to fit the cable.

maybe i can get lucky and there is a different speedo housing that might give me the clearance i would need.
I just wish i could find someone that did the dual disc conversion and would say that difference in offsets is what it is and everyone just lives with it.
guess i just have a mental thing for symmetry and this is just making me think that im doing somehting wrong
i would have thought it would have been brought up before.

Oddjob · « **Reply #21 on:** May 22, 2011, 01:31:31 PM »

As said I've done this mod, the bike with the Lesters on has done around 147,000 miles, around 120,000 miles were done after I did the dual disc convertion. At no time have I ever noticed any problems with the discs having different offsets, in fact until you mentioned it I'd completely forgotten that they had. No one in 30 years has ever commented on the discs being different offsets even though the bike used to win bike shows. I've had numerous CB500/550 owners asking how I'd done it during the 30 years, all to the best of my knowledge copied the way I'd done it although one did reverse the calipers so they hung at the back, not keen on that myself as it makes bleeding them far harder due to the bleed nipple not being at the highest point of the caliper.
Just do it and see if you like it, if not then look at other ways after you tested the setup for 6 months or so.

jaguar · « **Reply #22 on:** May 22, 2011, 05:21:50 PM »

thanks oddjob for the help.
i guess more of what was bugging me is that it seemed "off" and the last thing i want to do is put together something wrong and get hurt.

but if this is just part of how the dual disc conversion works then it is what it is.
so you remember now that they were like my pic?
amost 150K miles? any more pics of the bike?
i got alot of catching up to do..lol but then again im 26...lol

im sure the small offset will never bother me by looking at it. the lesters will make everything look great....lol

Oddjob · « **Reply #23 on:** May 23, 2011, 07:24:36 AM »

I do have some pics of the bike in question but I need them scanned into the PC and I don't have a scanner. My other CB500 has 263,000 miles on it so the Lester one is a baby by comparison, if I could have found another set of Lesters I'd have fitted them to the other bike but it has some mags on I found somewhere whose name I don't know. Never liked the spoked wheels myself, to hard to clean and the chrome used to start to fade after 10 years or so, still got them somewhere and no they ain't for sale before someone asks

If I can get my daughter to scan a few in I'll post the pics, the bike is stored at the moment as I'm using a CB1300, I'll be putting it back on the road maybe later this year after yet another restoration, new 4 into 4s, new OEM seat, new rear guard and might have it resprayed as the tank is a little grubby now after 30 years. Engine is still original in the main, never had a bore, clutch and gearbox still original and that's on both bikes, look after the engine and both the 500 and 550 will run forever.

I fitted braided lines to my conversion and used the master cylinder off a Yam until I found one off a CB900F2, stops like you wouldn't believe, I can lock the front wheel up if I wished, nevers tracks to either side under braking and just looks so much more balanced on the front end. Completely forgot about the offset but do remember solving the problem, when I did my conversion it was quite early in the 500s life, the 550 had just come out and as soon as I spotted the extra caliper mount on the right leg I just bought a written off 550 and converted the 500 with the spare parts, was pretty rare back then but it's a very common conversion now and much worth the effort to do.

News:

Author Topic: Dual disc question, K1 with lesters. (Read 2763 times)