Correct Rear Wheel Size?

[thomaskwscott]

Hi Guys,

According to some sites my ETZ251 should have a 17inch rear wheel but mine has 16inch. Is this right? Also regarding this i quite fancy having an 18 on the back with the extended suspension you can get from Ebay. Does anyone know if i can fit a 18 from and older bike?

Thanks

Tom

[therealche]

16" wheel is correct for the 251. Fitting an 18" will change the handling and require a change in gearing. I'll leave advice on that to someone who had done it!

[radiograf]

I bought my etz 251 with an 18" back wheel already fitted by a previous owner. It appears to have the longer rear swing arm from an earlier model,with all the adjusters etc to fit. The rear brake plate has the stop switch fitted into it as on the Supa 5, so I suspect all parts are fairly interchangeable. Can't help with the gearing though.

[thomaskwscott]

A little back of the envelope maths reckons the gearing change will be for a ratio of around 0.89, I think i can live with this as the bike always had plenty of pull. From what i can tell it will drop 30 mph in 3rd from 4000 to 3600ish, that would be a bonus for my commute....

Is a new swingarm totally necessary? I haven't looked but if i was to spoke a 18inch rimw onto my existing hub would it fit in the swingarm?

[thomaskwscott]

A quick update. Martin at Burwins sorted me out with the 18 inch rear wheel from an ETZ 250. It fits the swingarm but he did warn me that clearance at the top can be a problem (mines lifted 2inches anyway so not a problem). Looks like my maths was a little bit optimistic but the bike seems comfortable in 3rd all the way to 40mph now (this is brilliant for my commute).

I've attached a picture of the new setup (posty wash) showing the most important feature i've gained, it looks mean!!!

[radiograf]

What front mudguard do you have fitted?

[thomaskwscott]

The mudguard is from a '08 KTM 65, bought from Ebay for the princely sum of £4.25. To mount it i used some extra large washers to block the holes in the bottom of the yokes and ran some bolts down. In the end i had to create a 3rd fixing under the headlight to stop it wobbling about but i think it looks pretty good. These MX mudguards are all plastic anyway so a little work with the Dremel and they'll fit anything