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-   -   Will 18 inch wheel be OK in place of 17 inch in XT600E? (https://www.horizonsunlimited.com/hubb/yamaha-tech/will-18-inch-wheel-ok-45460)

Mark 22 Sep 2009 12:40

Will 18 inch wheel be OK in place of 17 inch in XT600E?
 
Hi All,

Does anyone know of any potential problem with fitting the 18 inch wheel from my crashed 3AJ Tenere in a 1991 3TB XT600E, which has a 17 inch wheel as standard?

I am hoping to keep a road tyre on the original wheel and fit an off-road tyre on the old Tenere wheel and swap that in for some green laneing. Has anyone done this? Is it likely that the tyre will hit the mud guard on full suspension compression. How can I check for this without taking the spring out of the shock absorber?

I am also intending fitting the old Tenere front wheel, with off-road tyre to the front, as they are both 21 inch I assume there will be no problem with this.

Thanks

Mark

Steve Pickford 22 Sep 2009 14:57

Fitting an 18" rear in place of a 17" will raise your gearing. You may want/need to compensate for this by fitting a smaller front sprocket or a larger rear sprocket, especially if riding off road. Onroad, you could see a slight improvement in fuel economy as a result.

It's possible to calculate by how much the larger wheel raises your gearing by comparing the circumferences of both wheels with the respective fully inflated tyres fitted and comparing one measurement against the other as a percentage. You then apply the percentage difference to your existing front & rear sprocket ratio to calculate the change needed to retain standard gearing.

To check clearance, remove your seat & place a ratchet strap around each side of the swingarm. Tighten the strap until the shock is fully compressed & check if the wheel's hitting anything.

cyberzar 22 Sep 2009 15:16

18" wheel
 
Had a 18" on my XT600E for one year, no problem installing it, no clearance problem with shock fully compressed.

21" wheel is exactly the same between XTE and tenere', had it on my bike for one year too.

now have XTZ660 wheels, both alu rims, rear 17", front 21".


Here a pic with tenere' wheels BikePics - 1990 Yamaha XT 600

bacardi23 22 Sep 2009 17:12

off topic... cyberzar.. that link of bikepics you posted.. shouldn't the guy have reinforced the frame because exhaust can isn't bolted on to the stock exhaust can mounting points??

Vando :confused1:

cyberzar 22 Sep 2009 18:02

I'm the guy :rofl: and used this setup for two years with no problems (no offroad). Now installed an inox metal tube, sagomed to replace standard exaust.

Have no pictures, but it's a really easy job, just get a plastic tube, hot air and make the model, then bring it to a welder and let him make it (with no holes) then go home and cut\make holes.

trophydave 22 Sep 2009 19:37

I have a mate with an XT600,sorry don't know what model,he has an 18 inch rim spoked onto the original hub.He uses trials type tyres no problem.

Mark 25 Sep 2009 13:24

Thanks
 
Thanks everyone for your thoughts.

It’s good to hear that this has been done before without complications, but I suppose that I should stop being lazy and use ratchet straps to compress the rear shock absorber, especially as it is an aftermarket one. I had justified in my own mind not doing this in case it put too much strain on the rear sub-frame, but it has been reinforced.

I hadn’t fully thought through the effect on gearing, but hope that going 2 or 3 teeth up on the rear sprocket would be enough. The whole point of the exercise is to be able to simply and quickly swap wheels to go from road to off-road use.

Thanks

Mark

cyberzar 28 Sep 2009 14:17

don't know if the straps system will work, but I'm not sure if you could damage your spring doing this... and compressed springs can be dangerous in any case.

Simply remove the shock, take the spring out, put the shock on the bike without spring. Put the 18" wheel on the bike, and test if all is OK, then assemble again the shock with the spring.

Steve Pickford 29 Sep 2009 08:44

I'm not familiar with Yamaha shocks but know from experience that a lot of OEM items are not that easy to take apart. Generally, it's the more expensive WP/Ohlins/Wilburs etc that have the threaded bodies that allow easily removal of the spring. You may still require a shock spring compressor?

If your subframe is weak enough to be damaged by compressing the shock via ratchet straps, then it's got no right being on the bike in the first place? I've done this to my 400EXC & 950SE with no issues.

cyberzar 29 Sep 2009 10:58

Sorry to disagree with you Steve, :thumbup1: all our bike's shocks have a thread, some on the main body, others on the lower part, for spring preload adjustment.
Remove the spring from the yamaha shock is easy, without spring compressor. Some of them have a clip under the top ring, that can be removed once the preload is fully opened.
You could need just a ratchet strap to shorten the spring a little.

Compress the shock with the spring on means apply a LOT of strenght that IMHO could damage the frame if done not on the proper point... and maybe the spring also. Consider also that using the bike the force to compress the shock is distributed under the whole seatpost, using a strap is not the same thing.

Furthermore, one thing is compress the spring for one second, another is to compress it near its maximum for one minute or more.

Jens Eskildsen 29 Nov 2009 19:32

Cool with the alloy xtz wheels.

Does the xtz use same hub as the xt from 90- ?

How about the spokes, does both the xt and the xtz ones fit?

I have a banged up rear rim on my 2003 xt600e, so info would be very helpful.

Thx.

Babybadger 20 Jan 2010 21:53

And vice versa, will a 17" fit on a XT600ZE? It will handle better, and you can compensate with gearing .... I find an 18" on the back just a bit of a handful...

cyberzar 21 Jan 2010 12:55

hub and wheels are the same (back) front has a bigger brake disk. You can swap them, no problem.

babybadger: what is a XT600ZE? please give me your model:

43F
3TB
4PT
55W
3AJ
...

anyway xt600 rear wheels are often the same (ok the disk brake ones) excluding TT600 model (TTR\TTE TT etc)

Must confess that did not feel that big difference between 17 and 18 wheel, having used them both...

dan66 25 Feb 2010 12:23

I had an 18" Morad ally rim spoked onto my original hubs using 9 gauge spokes and fitted with MT21 tyres. I found no problems even when fully loaded with luggage and bouncing through wadis.
The upgearing as a result was a bonus delivering higher MPGs.

Dan


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