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YZ front end on XT

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Can someone tell me where I can find info on how to install a newer front end off of a 2000 and up YZ250 on my 78 xt 500? I know it can be done, I seen pictures of Xt 500's with them on the bike, Any info would be Great.. Thank you..

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No tech write up for you, but the main thing is your going to have to use the triples so you need to concentrate on bearings and the stem of the frame. For bearings, you need to have tapered in your xt as that is what the newer bikes run. Honda 4t started about 80 or 81, not sure about Yami. Then you need to see if your stem is about the same length. you don't want to space it too much. The other option is to have your inner stem (threaded pipe on the lower tee) fitted into the lower triple tee on the YZ with a sleeve or something. Good luck.

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i'll be interested to hear how this goes, so please post your measurements when done -- i have a '97 YZ in the back of my garage that may get dissected if yours works.

i'm interested in swapping out my front end particularly because i want a front disc... but i'm also considering running some wider rims and taking the XT in more of a supermoto direction, which had me looking on eBay for SR500 forks & triples.

where did you see the pix you mentioned above??? did the rake of the bike look normal after the conversion? some of the inverted ones i've seen have the forks raised as high as they will go in the triples and STILL look like wanna-be choppers. in my opinion, it's always best to mess with the geometry of the bike as little as possible.

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Here you go 80XT500 these are the picture I found, Hope I did this right, This is the first time I did this, But anyway the bike with the silver and black tank is one bad mother. I just got a front end from fleaBay and wont have it untill monday the 12th. I'm good at making things work and I dont think I will have any problems with this. It would have been nice to find some info on this so I know what I'm dealing with but I wont give up. And when I do get it to work I will share all my info on it. Thanks guys for the replys. http://www.xt500.ch/fotos/umbautenXT500/images/XT500_100.jpg http://www.xt500.ch/fotos/umbautenXT500/images/XT500_322.jpg

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Looks like a pay web site, tryed to sign up but would not let me said I had to email someone. This place is cool for me.. Thanks..

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hey bishop, i've seen that first pic with the silver and black tank -- that's the direction i'm going. sweet bike. the second one is a perfect example of what i mean about the rake of the forks... ok, the front wheel is no longer a 21", so it's partly an optical illusion, but don't you think that looks like the bike's geos are way off???

still curious about those measurements, so let me know... and agreed on that other site -- i think maybe "brent" works for them or something

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hey bishop, i've seen that first pic with the silver and black tank -- that's the direction i'm going. sweet bike. the second one is a perfect example of what i mean about the rake of the forks... ok, the front wheel is no longer a 21", so it's partly an optical illusion, but don't you think that looks like the bike's geos are way off???

still curious about those measurements, so let me know... and agreed on that other site -- i think maybe "brent" works for them or something

Hey 80XT500 if you look at the 2nd pic the fork tubes are longer then the silver and black bike, thats way it looks like a chopper and the fender is shorter. I dont think that is a yz front end unless the guy with the silver and black bike had the tubes shortend. The yz front end I bought is the same lenght as the 500 front end.

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yep -- i think the second set of forks (bike with all silver tank) are too long. and that's a pretty janky brake caliper mount he's fabbed-up too. not sure if either bike has YZ forks or not... but the front end on bike #1 (black & silver tank) looks pro.

btw: are you planning to use stock YZ triples? and what about the hub and brakes? disc or drum?

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yep -- i think the second set of forks (bike with all silver tank) are too long. and that's a pretty janky brake caliper mount he's fabbed-up too. not sure if either bike has YZ forks or not... but the front end on bike #1 (black & silver tank) looks pro.

btw: are you planning to use stock YZ triples? and what about the hub and brakes? disc or drum?

You have to use the stock YZ trees, the upsidedown front end has bigger outer tubes then the stock XT tree and would not fit. From what I seen they some how use the XT shaft from the stock XT lower tree in the YZ lower tree. How they do it, I dont know yet. One guy here said you have to use the YZ upper and lower tappered bearings? I think that's alot of BullTaco, How would you get the race to stay in the frame? Any way, I need to pick up a front rim for the front end I bougth it did not come with one. But I will buy the stock YZ250 rim for it, But all I need is the hub because I'm going to buy the super moto rims for it. Also here is a link to another bike with lots of info on what he did to the bike. http://cgi.ebay.ie/1976-YAMAHA-XT500-SUPERMOTO-COLLECTORS-SPECIAL_W0QQitemZ110158628060QQihZ001QQcategoryZ9809QQcmdZViewItem

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You have to use the stock YZ trees, the upsidedown front end has bigger outer tubes then the stock XT tree and would not fit. From what I seen they some how use the XT shaft from the stock XT lower tree in the YZ lower tree. How they do it, I dont know yet. One guy here said you have to use the YZ upper and lower tappered bearings? I think that's alot of BullTaco, How would you get the race to stay in the frame? Any way, I need to pick up a front rim for the front end I bougth it did not come with one. But I will buy the stock YZ250 rim for it, But all I need is the hub because I'm going to buy the super moto rims for it. Also here is a link to another bike with lots of info on what he did to the bike. http://cgi.ebay.ie/1976-YAMAHA-XT500-SUPERMOTO-COLLECTORS-SPECIAL_W0QQitemZ110158628060QQihZ001QQcategoryZ9809QQcmdZViewItem

Hey 80XT500 here is some info I found on how to update are front ends, I'm telling you I will get this dam thing to work! Just cant wait for my front end to come!! The decision to fit a disc brake front-end to my 1979 XT500 was made as I slewed inexorably into the car that had just U turned in front of me. In the few seconds of realization that I was about to have a smack I noticed that the rear end was locked and skidding but the front wheel was still turning, despite the lever practically touching the handlebar.

Amazingly the only damage to the bike was a shattered front mudguard, somehow the 20mph impact into the side of the car did not bend the forks or result in any of the other usual damage!

After much research via the internet I found that the XT350`s forks are the same diameter as the 500`s (36mm)though despite posting requests at numerous sites I could not find a complete front end. I visited Allbike Spares in Greenwich and was given free rein to rummage amongst their fork collection with a vernier guage in my hot little hand, I found that the DT125LC and more modern DTR125 both have 36mm forks but didn`t feel comfortable with the thought of using a braking system designed to stop a weedy 125 2 stroke on a scale-bending XT500.

I was perusing the stock of Cheshire Motorcycle Salvage (www.cheshiremotorcyclesalvage.com) when I saw a Suzuki DR650 that was about to be broken, the huge disc(300mm) and long thick forks sold me completely and I emailed Paul the owner. He replied swiftly with the price of £250 for the front end complete, including P+P!!

It arrived with indecent haste and I was like a 6 year old kid on Christmas Day ripping open boxes..oohing and aahing. All the bits I`d asked for had been included plus a Renthall handlebar complete with all cables and switchgear, bark busters and a nice white brake disc shroud. Full marks to Cheshire motorcycle salvage.

Ok, this is the bit where I tell you how I joined the front-end onto the XT..if you have a highly technical background you might want to look away now. I`m the sort of mechanic who uses beer cans to make shims for handlebar clamps and tree stumps as centre stands.

The first thing I did was borrow a vernier guage and do some measuring;

the new steering stem diameters at the top and bottom where the bearings will sit and the diameter of the steering column of the frame at the same points. This is where I got really lucky, the DR`s steering stem diameters were the same as my XT`s...25mm at the top, 30mm at the bottom.

This meant that all I needed was a taper roller bearing set for an XT500. Dazed and confused at the simplicity of this ( I was expecting to have to go to a bearing stockist, chop and change, maybe even turn the cups down to a smaller size on a lathe,) I called Jon`s Scooters in Dalston to ask if a taper roller bearing set was made for the XT500, I realised that knowing my luck no such set existed.

`Yeah, we`ve got a set in stock..£40` said the nice man.

So I got up off the floor, jumped in the car and motored down to pick them up. While i was there I bought some brake fluid and new copper washers for the brake hose fittings at the caliper and master cylinder.

Arriving home again and with rain threatening I pushed ahead with stage 2. This is where I made a little mistake.

The length of the DR650`s steering stem is about 20mm longer than the XT`s, I`d made some 30mm and 25mm (internal diameter)spacers at work to fit at the top and bottom as required, but thought that as the taper roller bearings were 13mm deep and that the XT uses races with loose bearings(about 8mm deep)...the new bearings would act as spacers and I could space out at the top of the stem. I fitted the top cup into the steering head, nice smooth fit, then the bottom cup, then tried to get the bottom cone onto the stem. This I found really tight probably because the internal diameter of the bearing and external diameter of the stem are both 30mm.

I ended up assembling the bearing on the stem as best I could then inserting the stem into the steering column, then using the threaded collar to draw the stem up inside the column - thus pushing the bearing down the stem to it`s seat at the bottom of it. Did that make sense?

It worked fine but then I realised that I needed to have a spacer UNDERNEATH the bearing on the stem, and there was no way that the bearing was going to come off. The steel is extremely hard and has a tendency to shatter or chip if you hit it too hard.

The main problem was that at the top of the stem, the top cone sits around a 25mm diameter section resting at it`s lower end on a shoulder.

But because I hadn`t put a spacer under the bottom bearing the top bearing hit this shoulder before it engaged in the top cone. Now..,what would you have done? I decided to measure the offending distance and remove the shoulder with a grinder down to that depth so as to allow the two bearing surfaces to meet snugly. Aren`t Bosch 4-1/2" grinders great? If you haven`t got one..treat yourself. This cured the problem and the yokes were tight and snug, I used some of the 25mm diameter spacers on the top of the bearing then tightened up snugly with the loctited (is that a verb?) steering stem nut.

With that done it was just a case of assembling the front end, it was basically plain sailing from here on, I think the sun even came out at one stage.

I was sorely tempted to leave off the headlight and front mudguard, it did look awfully nice without them, but common sense prevailed,,I think I might fit an enduro style headlight unit at a later stage - the original XT headlight looks dated indeed nestled amongst the liquid shininess of the DR650`s forks. Neither speedometer nor tacho will be re-fitted.

I`d noticed that the steering stops on the bottom yoke were in a different position, turning the bars to the left the top of the fork touches the tank, turn to the right and the stop hits early, so the grinder came out again and I touched the right-hand stop on the frame down a little until the fork came within a reasonable distance to the tank.

Before test riding it I went over every nut and bolt making sure it was all buttoned up right, then before riding off I turned the bars to make sure the throttle and clutch cables operated smoothly without snagging.

Did it work? Damn right it did, although the forks look much longer than standard there doesn`t seem to be any detrimental effect. The wheelbase is definately longer but the bike still feels nimble, perhaps a very slight tendency to `tuck-in` but that might be the extremely worn front tyre that came with the wheel. The front brake is absolutely awesome..more than capable of performing a `stoppie` if only I had the guts ( and jock strap ) to try one.

If you have an XT500 with a drum brake I would seriously recommend this conversion, it looks great and one day might save your life.

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hmmm.... i'm not so sure about this guy's eagerness with the grinder. and all of those spacers???? note how he mentions that the "forks look much longer" and how there "doesn't seem to be any detrimental effect" -- that just screams raked-out chopper to me. my guess is that anyone with this kind of hammer-the-square-peg-into-the-round-hole approach wouldn't notice if the handling was off on his bike or not anyway. he better hope those bearings stay good forever (which they won't if he ever starts pulling "stoppies").

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Hi there,i put a TT600 front end on by removing the stem from the triples on the XT and they press straight in on the TT600 triples,upgrade the ball and race with taper rollers from Thumperstuff and you are away.Your next thing will be to fit longer rear shocks unless you want a chop look but the geo will be up the pole if you dont.To stop the forks whacking the tank i drilled and tapped 6mm holes into the stops on the TT triples and put in 6mm cap screws with a locknut.I didnt have the same turning circle but it was fine and the conversion was worth it,no more fork flex under steam and braking was better.I could only get the forks with a double leading edge drum but i should have looked harder and longer for the disc brake model.Being on budget at the time i used Suzuki PE 175 rear shocks,you can use the rear swingarm from the PE250/400 for a longer swingarm which looks pretty hot and gives you a better geo as well.

silverlion.

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