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As a guy who started on quads, I can really appreciate this. Smart choice to use the quadracer engine vs. the dirtbike one, that counter balancer should keep it nice and smooth.

What year engine did you end up using?

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Discussion Starter #5
Thanks Guys. I agree, the motocross motors are hard to ride on the street, period. I've ridden a few and wanted something with use-able mid-range so i can actually ride the thing, not a huge explosion of power. I considered a few motors but a Quad motor seemed like the logical choice, and the counter balancer was a HUGE plus. Also, comes factory with 12v lighting setup so that made things easier. and size and packaging. I -did not- cut the frame except in 2 minor ways. the stock upper mount was removed, and i relocated/angled the LH side sub-frame up and in to clear the uni filter which now sits behind the seat latch mechanism .

I broke the rod in the grom motor before may, so at the 2 stroke meet at deals gap i put my feelers out, and this came up. its completely rebuilt (i got it apart) and everything internally is new.
Its an 86, pre power-valve motor, so I did make a concession there.
It IS run through the stock harness, everything works. I was going to run it through a flashed ecm but DHM answered me once, and then ghosted, so whatever. I used a zeeltronic programmable cdi unit controller and went that way instead. Boysen reeds, custom tig welded stainless intake , cr125 radiators with filer relocated and pipe tubes reclocked a bit to fit. no loss of turning clearance, nowhere near the front tire, all tucks in under the bodywork.

the pipe is a stock unit, reclocked a few times and rewelded, and only loses 1/8" clearance over a stock grom.
all motor mounts are hand made and bolts in. rear are laser cut 1.4" steel, lower is 3/4" dom tube, and front is a ladder cradle from dom 3/4 to a lug welded in under the neck, which also has the 2 legs to hold the fairings out added to keep the floppiness of the body work to a minimum.

It does rev really smooth. I need to get the timing curve finalized and the jetting sorted. Im getting a bit of RF from the pickup, soi i need to add an rf drain and a ferrtite choke to the cdi wiring but thats pretty common with the unit im using.
Also went back to stock rearsets for kickstart clearance and just simpler to deal with.
I did all the work myself, except the tig welding on the stainless intake, my friend David wanted to do that for some reason, and one part of the radiator fab work. I think he was just bored and wanted something to do while his bikes frame was out for poweder coating (KZ650, old header is in the pic ahead of the grom).

heres a pic from 2 or 3 weeks ago, shows the intake, carb placement, and front mount. the pipe looks fucking ridiculous.

85773
 

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Banshee owner over here... that admittedly searches for an LT250R project at least 4 times a week!

You got the good year too, what is it 87 and up that the reeds are on the outside of the cylinder?

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Discussion Starter #10
i believe so, this has the weird hybrid reed/piston port configuration, with the reeds case inducting. i was very impressed with the port layout as well. pretty advanced for the early/mid 80s.
 

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Banshee owner over here... that admittedly searches for an LT250R project at least 4 times a week!

You got the good year too, what is it 87 and up that the reeds are on the outside of the cylinder?

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The 1987 and up got the powervalve. I'm going to sell my '91. I just haven't listed it yet because I don't want the public coming to my house to check it out so I'm not sure how to go about doing it. LOL
 

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NICE work! I use to own a 86 QR, loved it! I ported the crap out of it, and cleaned up/flowed the cases some too. Thing was kicking my buddy's Banshee's azz all over the place until he hit 6th gear, then he slowly caught up. Soo much fun back in the early 90's when I lived in PA.
 

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Discussion Starter #14
done. Final Update:
Just need to change gearing a bit, runs out in 5th way too early, so have a few smaller rear sprockets coming to dial it in. Front is already as big as will physically fit. Got hung up on some cdi issues, other projects, and shitty weather. Rode it to work today, its a riot. super strong midrange.
86229


86230
 

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Discussion Starter #15
as a 'final' update: gearing in at 14/30, but more tuning and i got 31mpg mixed riding around town, have around 150 miles on it since last post. been very solid so far. took it to dealer i bought bike from new, let the sales manager take it out for a ride as well, came back impressed, stood it right up it in 2nd gear right out of the lot. lol. (we've actually been friends for years). Next up is a bigger fuel capacity on a spare tank i have to mod, then its going to the 2 stroke meet at deals gap in may.
 

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Pretty damn cool...
 
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