supermoto
 

has anyone made a supermoto out of an xt600 3aj or have any suggestions about what wheels would fit spacers upgrading brakes etc or would i be better to get a ttr600 and build this up it just happens i have a spare 3aj doing nothing. thanks

Are you intending to fit cast or spoked wheels? Cast are easier to locate & you'll have a greater choice but check them carefully if buying from a breakers.

I've got 1100EFE forks & yokes in my DR600 with an FZR600 wheel, EXUP disc & GSX-R1100 caliper. The yokes went straight in, with the aid of a spacer from a GS750. If intending to use cast wheels and the original forks, check the distance between the inside of the fork sliders as trailbike forks are generally closer to together than regular road bike forks. I went for the fork swap as there was no room for speedo drive. Digital bicycle speedo (cheap) or one of the aftermarket enduro speedo/trip computers (expensive) as advertised in TBM are other options. The greater hub width on wide cast wheels is the problem. Big discs and different calipers mean one off caliper mounts also.

I fitted an RGV250m rear wheel to my DR.Once again hub width caused problems. The width of the RGV caliper mount had to be reduced by machining the outer face and the spacer on the left protruding from the sprocket carrier only sticks out by 1mm but the wheel is central.

Converting from a drum rear to a disc rear present their own problems, as do tyre width, caliper torque arms.

I managed all of the above myself, with help of friends with lathes etc. Paying someone to do it is not cheap, as is getting wider 17" rims laced to your original hubs (£500 plus tyres, disc etc). Try looking in TBM or Supermoto magazine, there's usually wheels etc for sale in every issue.

Good luck

Steve

i just got new wheels laced onto old hubs, secondhand complete with tyres. if you want to go the whole hog with uprated brakes, suspension etc then a whole new front end would be the best bet because hop-up parts are rare+expensive unless you can make your own.
re; speedo, i worked out the difference in readings between the old 21" and new 17" wheels and marked the speedo face accordingly. the speedo will read about 16% too fast with a 17" front wheel.
this has worked great but ive seen on the new husqvarna450 a lovely setup with a bike computer in a backlit housing with built in idiot lights. to buy as spares will cost about £70.

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dave

Thanks for advice.
I have just bought a TT600 allready supermotoed as I think its cheaper then changing wheels etc.
I do like the idea of a digital speedo is this difficult to set up?
Any advice on starting the TT it is 98 model no battery kickstart only.Sometimes it will fire up and die or a bit of smoke will puff out the exhust,Is this flooded?if so what to do? the previous owner did go through the starting routine but i think i may have flooded the engine.It also has a CJD cam fitted?Could this affect starting?
Also any good TT600 webb sites
Thanks for any help Bolla.

I am in the process of motarding my 3AJ too.

Unfortunately there is no cheap and easy solution to installing 17inch rims. I am going to get rims laced onto my existing hubs (500 quid is about right).

However I would advocate against swapping forks for a road bike's. Reason is that the appeal of supermotos for me is the (almost) all-terrain capability of road wheels with dirt-bike suspension. You need the long travel to soak up potholes etc on tarmac. Check out the suspension travel on factory supermotos - they are all of similar length to the 3AJ/TT's stock.

Fitting a complete front end from another bike is unlikely to be cheaper than uprating the existing set-up. Also this is a more complex and therefore less elegant solution (if that's important to you).

Search the net for Rach Tech Emulators. These little gadgets cost 100 quid for a pair, and fit inside your existing forks. They turn your forks into new style cartridge type items, which provide firmer damping under brakes and softer damping when the front wheel encounters sharp bumps (read the bumph on their site for a full explanation). I'm going to install these on my travel bike too.

There are plenty of places in the UK that will CNC machine an oversize brake disc to fit your rim for about 160 quid. I bought a Braking supermoto caliper on ebay for 120 quid, add another 150 for a new master cylinder and caliper bracket. Total 530 squid (excluding the rims) for a quality and easy-to-install front end. Compare this to the cost, time and effort of finding and grafting on a front end from some other bike.

Of course, it's all a matter of personal opinion and preference. Does the TT you bought have standard suspension travel and standard hubs?


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Barry
3AJ Tenere

All kickstart bikes feel different when trying to start them.

Practice turning the bike over & trying to recognise when it is just past TDC - once found, this is the time to give a good kick. Modern singles, IMO tend to have lightweight internals with a high compression ratio requiring a short sharp kick compared to my friends Panther 600 which has very heavy internals but a low compression ratio needing a long slow kick. Other factors that can affect ease of starting is kickstart length and the the primary drive ratio.

At first, keep the throttle closed and use the de-compressor lever if fitted. Find out if the carb has a pumper fitted, if so, be wary of too much throttle or you will flood it. Sometimes they can be hard to start when warm, but okay when hot. My DR usually requires the choke & plenty of throttle in this istuation. Cleaned & gapped plugs and a well adjusted de-comp. cable all aid easy kick starting.

Injury can result if you get it wrong; my old XL500 kicked back when wearing jeans. My foot slipped off the kick start & the serrated footpeg went through my jeans and removed a 6" long strip of skin from my shin - you cann ot imagine the pain, blood & tears! Turns out that the de-comp. cable had snapped. I actually managed to start the bike by hand until I had a new cable, by leaning over the bike & keeping my face out of the way in case of kick back.

Take your time and vary your technique, you'll find something that works for you.

Steve

bolla,
a digital speedo is very easy to set up, ask the thousands of kids with them on their bicycles!

more difficult is ensuring it doesnt get stolen, most are made so that you can unclip the unit and take it with you, great until you forget to take it off! also ive never seen a cheap one with backlighting, needed for your MoT.

the one i saw on the husqvarna was purpose made to get around these problems, but thats why it was £70 odd! bicycle computers start at £5ish.



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dave

Problem with bicycle speedos is a lack of accuracy if you follow the instructions, which usually involves entering the wheel circumference.

The circumference of a 17" sports tyre is about 1800 - 1850mm. We measured twice, once with a tape measure around the wheel & then again by measuring the radius etc, arriving at a similar figure bith times. This resulted in a 200mph bike if speedo was to be believed......

Enter the measurement but be prepared to keep on entering smaller or larger figures dependent on speedo under or over reading. Make a note of your bikes speed at a certain rpm in top gear & use as a guide. Keep trying until the speed is correct for that gear & rpm.

We eventually settled on a figure of 1300mm, not 1800mm......

Most speedos don't have lights but you can buy an attachment that clips on to the h/bars.
Steve

its no good measuring it that way, theres a flat spot on the bottom of the tyre from the weight of the bike, and the working circumference of the wheel will be slightly smaller than what you can measure. not a lot smaller, but enough to change the circumference 4 or 5 inches. put another way, you will be going 8-9% faster than your speedo is saying you are, on top of the 10% allowed by law.
fancy those odds against a GATSO anyone?

stand the bike upright with the tyre valve exactly on the bottom of the wheel. chalk a line on the ground, wheel the bike forwards until its in the same place and chalk another line. measure between the lines, and theres your circumference.

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dave


a mate has a kawasaki W650, a lovely 60s style bike. she can use the kickstarter with one finger, its like a sewing machine! another mate had his shin broken by his husky 610 kicking back. OUCH!

[This message has been edited by DAVSATO (edited 25 October 2003).]

I take you point on the flat spot but this in no way accounts for the discrepancy in figures that we needed to input.

Steve

good point, i guess they vary wildly in accuracy. unless you spend quite a bit of cash getting a very good one, they are just "toys" really, and i dont suppose they are tested to any sort of standard.
anyone know of any that are?
i always thought that any aftermarket speedo you fit has to be BS rated (or the EC thingummy now) to get through an MoT, but all these supermoto guys seem to have no trouble. maybe its like a competition exhaust, it "dissappears" at testing time? ive just got little number stickers on my original dial, thats been through 2 tests ok.

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dave