cr80/xr80 hybrid?

[mainline]

Has anyone ever looked into grafting an xr80/100 motor into a later model cr80 (or similar) frame? I was thinking of something with good suspension and brakes but more user (and neighbour) friendly than the 2 stroke.

[Momus]

It's a very popular conversion with the XR100 motor being the usual choice.

 file:///C:/Users/Marcus/Desktop/SoCal%20XR's%20Newsletter.htm

I have a nearly completed XR100/Takegawa145 in an SX85 KTM chassis.

[luigi37]

http://www.socalxrs.com/

have a look at these , good for XR and TTR125 etc any aircooled hot rod mini.

[Nathan S]

Did you see any of the "Backyard SX" articles in US Dirtbike? Not overly detailed tech articles, but enough to show that it's been done more than once before.

[Tim754]

That conversion used to be a class in minibike racing in Victoria. (Old Victorian Junior Motorcycle Association ( ? )prior to amalgamation with MA. )

[Momus]

Langtown in SoCal.
Once the holy grail of backyard Supercross;
150 cc 4 stroke, any chassis.

https://www.youtube.com/watch?v=v6Qnw5LK3Lo

Now, after being noised out, the track is used for a novelty race for mountain bikes.

[tony27]

You mean this one?
https://www.youtube.com/watch?v=LE7lEF3R9dM

[Doc]

not a CR chassis but...

[evo550]

Wouldn't  it be easier to graft better suspension onto the xr chassis?

[mainline]

Wouldn't  it be easier to graft better suspension onto the xr chassis?

I think i'd rather have this

[Momus]

Wouldn't  it be easier to graft better suspension onto the xr chassis?

XR frames are weak when jumped; no under engine tubes and the backbone bends.

The rear shock is very short and limits travel to about 6". CR85's run about 11" at rear.

[evo550]

Wouldn't  it be easier to graft better suspension onto the xr chassis?

XR frames are weak when jumped; no under engine tubes and the backbone bends.

The rear shock is very short and limits travel to about 6". CR85's run about 11" at rear.

Works do a shock for them that gives then proper action and a couple of inches extra travel, that combined with mid '80's cr 80 front end would be a good little combo.
It's never going to be able to do 120 ft tabletops as they simply don't have the juice. They usually struggle to get up the up ramp.
They are great bike for what they are designed for, but Mx isn't it.

[FourstrokeForever]

Here's my XR/CR80 Hybrid. Built more for show than go. I can't see myself ever wanting to race around on an XR anymore. I have bigger toys now 

[mainline]

Here's my XR/CR80 Hybrid. Built more for show than go. I can't see myself ever wanting to race around on an XR anymore. I have bigger toys now 

That is a beautiful bike. I wasn't thinking of a bike for me to ride though. I was looking for something for my son. There seems to be a big difference between "kids" bikes and race minis these days that i don't think was the case in the 70's and early 80's.  Something with a quiet user friendly engine but a good frame and suspension just isn't available off the showroom floor.

[FourstrokeForever]

Thanks. I like how the bike turned out.
There's nothing wrong with the Honda CRF range. Sure, they don't have "race spec" suspension but they meet the demands of a semi serious play bike. I have a CRF230 that I got for the better half and it's a really fun bike to ride. I gave it a bit more oomph with stiffer springs front and back, opened up the airbox and put a twin air filter on. Full BBR exhaust with the optional Honda carby needle and jetting. Goes pretty good for an air cooled baby 4 stroke. It hardly ever gets ridden though so I am thinking about selling it.