Lightest wheels for a slingshot

[MeanBean49]

1 hour ago, markfoggy said:

Ok Folks, there will be some delay here gathering data.

I have a tyre fitted to my pre '12 wheel so cannot get a straight edge across the rim. Can't move the tyre for a while now, and it will be inconvenient. 

First appraisal though is that the bearing faces are a common width, but the disc mounting face of the later wheels is further inboard and the disc PCD is smaller.

Simple answer is the wheels are not interchangeable.

My cushdrive rubber is brand new so getting a true figure for inner sprocket face to rim is proving difficult as well, I have no arm here to clamp it up in, but it seems to be about 27mm.

 

 

I dont understand the relevance of this "data" to anything whatsoever?

[CockneyRick]

3 hours ago, MeanBean49 said:

Please do. Pretty sure Srad boys wouldnt be bolting k series rear wheels straight in otherwise.

The ones in my garage all measure the same 110mm ish from wheel center to inside of sprocket face

I'm talking about the full hub width, not the sprocket side half! What's the point in measuring only half a hub?

[dupersunc]

32 minutes ago, CockneyRick said:

I'm talking about the full hub width, not the sprocket side half! What's the point in measuring only half a hub?

That determines the offet between chain line and the centre of the wheel.

The measurement between the centre line of a slingshot chassis and chain line is 'x'.  The measurement from the centre of a srad/k series wheel and sprocket is x+10mm. 

To centre an srad/k series wheel in a slingshot chassis you need to correct the 10mm difference in chain line.

The offset of this rear disc is a separate issue.

[MeanBean49]

13 minutes ago, dupersunc said:

That determines the offet between chain line and the centre of the wheel.

The measurement between the centre line of a slingshot chassis and chain line is 'x'.  The measurement from the centre of a srad/k series wheel and sprocket is x+10mm. 

To centre an srad/k series wheel in a slingshot chassis you need to correct the 10mm difference in chain line.

The offset of this rear disc is a separate issue.

Exactly. The 2 most important things, get it central and get the 10mm off the centre to sprocket. If you havent done this then the whole job is a bodge

Ant theres more than enough meat on a caliper hangar if you need to machine it down to fit. Iirc though disc side wheel centre to inside face of swingarm is virtually the same between all models.

[markfoggy]

Ok, 150 and 200 mm digital verniers, 600mm rule, 300 mm rule and a 150mm rule.  Much juggling.

A TPot 675 Rear wheel comes in only one size,  5.5" x 17, but 2 iterations.

Pre '13 is the 5 spoke, round spoked, cast looking wheel, the later looks like a forged rim but is a casting, it has holes at the end of the spokes.

The sprocket carrier hub is common and fits both wheels. 6 x M10 stud, PCD is 125. Cush drive rubber is common.

Takes 20mm spindle.

Wheel bearings and seals are common, width across the bearing outer faces is 171mm.

Circlips are common and single sided wheel bearing goes into a landing on the circlip side, circlip is installed, spacer comes through from the other side and then second bearing is installed against the crush spacer. Crush spacer dims are accurate, you will not find that you need to play wiggle the spacer on these wheels.

Getting this measured was complicated, think bitch. You have a 6 landing sprocket carrier, a 5 spoke wheel and a 4 landing disc mount surface. Getting tools in to measure is not easy if you don't have access to surface plates and height gauges. It gets worse if you are trying to do this in your front room and have no space.

Early 5 spoke.

width across the rim is  159 mm

width across bearings is 171 mm

this is common with the later wheel

L/H offset C/L to inner sprocket face is 106 mm with standard spacer fitted to the sprocket carrier.

 

this is common with the later wheel

R/H offset C/L to inner  disc face is 83 mm (I may be +/- 0.25 here, best I can do)

Rear disc PCD is 125. O/D 220.

Later post 2012 i.e. 2013+ wheel. 

width across the rim is  162 mm, looks like a proper redesign

width across bearings is 171 mm

this is common with the earlier wheel

L/H offset C/L to inner sprocket face is 106 mm with standard spacer fitted to the sprocket carrier.

this is common with the earlier wheel

R/H offset C/L to inner  disc face is 78 mm

Rear disc PCD is 100 mm. O/D no idea.

So when they bought in the later wheel, everything stayed the same on the drive side of the bike.

What they did, however, was slim down everything and particularly the central hub.

The rear disc on the later bike is 5mm further inboard and the mount points are a much smaller diameter.

 

 

 

 

[Oilyspanner]

Here's the weights for some of the wheels mentioned, I weighed a number myself on the same scales, a few are from other people's findings.

Twisted spoke     3.5 x 17  with bearing and spacer   -     11lb 10oz                    5.5 x 17 complete   -   16lb  14oz

Straight spoke     3.5 x 17              "                                 -     10lb 5oz                       5.5 x 17   "               -    14lb 8oz

600/750 K8 - L0   3.5 x 17              "                                -       9lb 2oz       L1- on  -   5.5 x 17    "              -    11lb 3oz

1000 K5 - 8           3.5 x 17               "                                -       9lb 4oz                        6.0 x 17    "              -    12lb 1.5oz

Above - same front as 600/750 K6 - K7

T675R                    3.5 x 17         with bearings ?            -       8lb 4oz                         5.5 x 17  " ?              -   11lb 2oz   - not my figures

cbr600rr 07-12      3.5 x 17   with bearings and spacer -     8lb 9oz                          5.5 x 17   "                -   11lb 7.5oz  - not my figures

Sprocket carriers  twisted spoke   2lb 12oz    - straight spoke carrier     2lb 3oz    -  the  L1 on carrier with integral sprocket bolts, spacer and cush rubbers is 1lb lighter than the straight spoke carrier with the same included.

When I was looking at fitting newer/lighter wheels, I did notice that loads of T675R front wheels weren't straight - delicate ? - not like the old Slingshot wheels which are very tough.

 

 

[markfoggy]

Just as a matter of interest ..

What is 11lb 8 oz in old money??

[Captain Chaos]

18 minutes ago, markfoggy said:

What is 11lb 8 oz in pre-brexit money??

fixed

[markfoggy]

Ha, Ha Not fixed

 

[MeanBean49]

42 minutes ago, markfoggy said:

Just as a matter of interest ..

What is 11lb 8 oz in old money??

Ask google. ;-)

[vizman]

3 hours ago, markfoggy said:

Just as a matter of interest ..

What is 11lb 8 oz in old money??

that is 'old money'

[markfoggy]

Can't find Imperial Google, do I need to log on through a Proxy Server based in the US? 

 

[bluedog59]

5.216 Kg.

[Oilyspanner]

I kept to lbs as I had the weight of a standard GSXR1100M/N in lbs with a full and empty tank and used that as the basis to work out the bike's weight  as I fitted lighter parts - just didn't convert to metric. Does Brexit mean we can sell fuel in gallons again ? !   Metric makes sense as we count in base ten, but many years of dealing with lbs and oz  still makes me convert kgs to lbs - although who in the first place thought using units broken into 16 parts and others of 14 made any sense at all !!!!! - did they have 16 fingers  ? - knew a chap with 12 once.........

[vizman]

.....crops....grain.....the first stuff we could use as a baseline of measurement.

[banoffee]

1 hour ago, vizman said:

.....crops....grain.....the first stuff we could use as a baseline of measurement.

Do we need to create a bartering section in marketplace? Maybe call it ‘Bartertown’ 

[vizman]

.....who runs Bartertown?

[MeanBean49]

11 minutes ago, vizman said:

.....who runs Bartertown?

Your definately more master than blaster haha

[Jay_111]

It sounds like the 675 wheels are the way to go then given the width and more importantly the weight. If only someone would produce a fitting kit.. lol.

Once the bike is back with me work will start on this conversion. Unfortunately I have limited experience in this area but that won’t stop me trying. The front I can handle, the rear will obviously be more tricky. I don’t mind spacing out the front sprocket a small amount but getting offset ones doesn’t sound like fun. With a bit of luck, judging by what @dupersuncsaid, it may be an easier job than some, and hopefully  without having to machine the hub..We will see. If anyone else fancies this conversion and or is doing it already then any shared info would be cool. @markfoggy

Cheers

Jay

[dupersunc]

4 minutes ago, Jay_111 said:

It sounds like the 675 wheels are the way to go then given the width and more importantly the weight. If only someone would produce a fitting kit.. lol.

Once the bike is back with me work will start on this conversion. Unfortunately I have limited experience in this area but that won’t stop me trying. The front I can handle, the rear will obviously be more tricky. I don’t mind spacing out the front sprocket a small amount but getting offset ones doesn’t sound like fun. With a bit of luck, judging by what @dupersuncsaid, it may be an easier job than some, and hopefully  without having to machine the hub..We will see. If anyone else fancies this conversion and or is doing it already then any shared info would be cool. @markfoggy

Cheers

Jay

Bring the Wheels down Jay and we'll have a proper look.

[MeanBean49]

2 hours ago, Jay_111 said:

It sounds like the 675 wheels are the way to go then given the width and more importantly the weight. If only someone would produce a fitting kit.. lol.

Once the bike is back with me work will start on this conversion. Unfortunately I have limited experience in this area but that won’t stop me trying. The front I can handle, the rear will obviously be more tricky. I don’t mind spacing out the front sprocket a small amount but getting offset ones doesn’t sound like fun. With a bit of luck, judging by what @dupersuncsaid, it may be an easier job than some, and hopefully  without having to machine the hub..We will see. If anyone else fancies this conversion and or is doing it already then any shared info would be cool. @markfoggy

Cheers

Jay

Sounds like it could be fairly straigt forward. Captive spacers should get tge spindle diameter down and make wheel changing easy, and if you went to a 520 chain it would give you space to space the front sprocket out to match the rear without any machining

[Oilyspanner]

Would make a good write up chaps - what's needed for T675R (I think the street triple use the same wheels) wheel fitment. 

[Jay_111]

9 minutes ago, Oilyspanner said:

Would make a good write up chaps - what's needed for T675R (I think the street triple use the same wheels) wheel fitment. 

Yeah will definitely write it up if I can get it done. 

[Upshotknothole]

Those 675 wheels are light, but I've seen the front and rear destroyed on friend's bikes when they've hit pot holes on the freeway here. Not really sure how durable they're going to be on an even heavier bike. Also trumpet oem parts and bits are fucking over priced.

[Mole28]

So, if I'm fitting an SRAD wheel to a slingshot, which part(s) of the sprocket carrier do I need to get machined and how much?