crf70 build

[sean01]

Well iv been planning this build for a while and have just been slowly collecting bits and pieces together.
The TTR shape never really appealed to me so I thought id convert it to a crf70.
The chassis is from Revmx with different coloured hubs..

So basically the part list is as follows..
Revmx frame and swing arm
DNM M200 forks and clamps
DNM rear shock
CRF70 Seat and Plastics
Revmx Wheels with gold hubs (not what I wanted but will do the job for now)
Revmx Brakes (front & rear)

And pics of all my parts when they arrived. (theres also some for a 10’ build im doin)



Im still sourcing some other parts and I am wanting to replace/upgrade the linkage system as it just doesn’t seem like it will last long.. the main concern is the bushes for the bearings, there only made from soft mild steel which I doubt will take the flogging im going to give it..

The engine is a bit of a mix. It started as zonger 155 which I purchased off woggy with a V2 head.
The engine needed a new crank which I replaced with a slingerless yx160 crank.
The bore is a 67mm akunar kit.
The V2 also needed the valves replaced so I got some from DHZ and lapped them in.
I’ve also opted for the yx150 daytona copy clutch cover.
The V2 copped some more port work as the last person that did it went to a great deal of trouble doing just the ports and left the important area’s, so basically I ported the bowls and under the valve seats and also the short turns were up to sht..so its all sweet now..

Will be interesting to see how well 200cc holds up in a linkage bike as the engine doesnt get the abuse that it would on a crf50 style build..

ok next lot of pics are to show the sub frame mod..
it had to be bent, stretched, welded, hammered, you name it i had to do it..lol even had the portapower on it at one stage..

standard setup all assembled and waiting for chopping..


stepping the rear section up


checking things out


all painted and ready to go..


and this is where im at with it now
its got woggy's old lxr pipe and muffler on it for now, but it will get replaced later on (as will a lot of parts) as my main aim at the moment is to have this ready for the black duck valley ride day


Parts im still waiting for..

Fat bars
Clutch lever and perch
Kill switch
Coil
Linkage parts
and some other odds and ends and of course a sticker kit.

 

[Hillz]

WOW, this is going to be one bad machine!

 

[sean01]

yeah, hopefully bad in a good way lol

 

[MiniFighter]

Looks great Sean! cant wait to see it finished.

Any ideas on graphics?? pretty limited colour wise with the white plastics?

 

[sean01]

no idea at this stage lol, its the last thing on my mind.
but i didnt really want white plastics but thats all my mate had in stock at the time..
and i needed them right then and there to mock the frame up.

i'll probly get another set.. i want red with white side guards..

 

[wogtaz ryder]

Looking sweet as , much better then ttr style

 

[pb performance]

Yeah, What woggy said.......

 

[AussieMX]

tell me how the forks go when your done, looking at making a crf70 and was looking at those forks on tbolt.
Cant wait to see this finished.

 

[sean01]

well everyone else thats used them said there good but they need an oil change. which i havent done yet as i want to try them in standard form first..

 

[bradisfun]

awesome build sean, just looks a little bland and standerd but its defiantly anything but standerd haha
just think she needs some more color... and some action pics
it'll be good to see how she lasts with that much power too.

 

[Carlts]

Wow Sean that is an awesome build... I wonder if it will compare to my SSR 160r jokes mate
I love the frame modded to fit the crf70 plastics looks very nice.

nice table btw

 

[sean01]

ok bit of an update...

id like to thank Sam, the bars showed today.. cheers mate.

so anyways. i obviously put the bars and what not on and i purchased some pillow top grips and a pro taper bar clamp pad.

also went to the bolt shop and purchased a full set of unbreako allen key headed bolts for the engine and various bits on the bike.. 99% of the bolts are allen key headed.

i also fab'ed up the rear brake caliper bracket as i wasnt sent one. (not painted yet)
wiring is finished.
installed a set of HD clutch springs as well.

theres some other bits iv put on as well.

and im waiting on some bits from DHZ to show tomoz..

any how heres some more pics..



so slowly getting there..

oh also i got a forged kick starter but sadly they dont fit the yx daytona clutch cover as there is a bolt directly behind it which interferes it would also hit the clutch cover.

 

[fusedminis]

Im pretty sure you can mod the kicker, at least I think I have seen this combo used before, possibly on PM.
As for the rear brake mount, it looks the goods. I have a couple floating around that you can have for free (you pay the postage) if you ever get stuck.

 

[wogtaz ryder]

 

[sean01]

yeah i modded the kick start lol... had no option but to weld the base of a standard one on it to space it out as well as still being clamped.. it looks dodge but works.. i wanted to ride the bike today so i could iron out all the little problems that might show up..
still need to do a final tinker with the carb but i have to order a needle..

the only problems that i had was
1. Hard to start... i really need a decomp on this thing.. originally it had about 13.5:1 comp and was a b!tch to start so i lowered the comp last night to 11.5:1 which is safer anyways..

2. Front forks need some work... lighter oil will fix that.

3. Rear brake line busted out of the caliper banjo. lucky it was at the end of the days riding..

4. Did i mention it is hard to start lol....

so things that are still left to semi finish my build includes..

sticker kit
re-lace the rims to H/D rims..or simply just replace the both wheels.
might change the whole rear setup as im really not happy with the swingarms strength and look..
new tyres, as the front is really skatey (millville) i want a 70/100 so it will steer better.
change the clutch lever and perch as its only one i had laying around..
extend the rear brake pedal so its not so touchy..
another oil cooler or 2 (replace the current one)
want to replace the 1/4 throttle with a standard turn throttle, its really hard to ride slow lol..
need to replace the rear sprocket to a smaller one as 1st gear is seriously useless, and thats with lifan 140 primary gears too.
want to change the exhaust also.. i blew the a$$ out of woggy's pitster muffler today.

more stuff will pop up that i want to change, but like all bikes builds. there always never close to being finished.

anyways here a short vid of my mate having a chop on it today..he quickly got addicted to the power as even in 4th gear and pulling the throttle on it just loses traction.


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[wogtaz ryder]

Looks like it hoooks! hopefully holds up for blackduck lol

 

[sean01]

yeah, i was actually waiting for sht to break in the engine today lol.. starting it is super hard and kicks back big time.. (touch wood)

 

[sean01]

ok, did a few little tweaks today.

changed the rear brake pedal.. modified this HD Footpeg Mount , Rear Brake Pedal Kit - DHZ Mini Moto works heaps better now as the other was a shade too short and rear touchy.

cut and welded the exhaust so the pipe wasnt so close to the clutch cover.. i can now fit the second cooler.

changed the rear sprocket from 41 down to 37 which made the power more usable.

anyways here's another vid from a front yard bash..


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[sean01]

thought id post what the bike looks like after about 10hrs of riding...

iv had no problems with the bike itself apart from flat-spotting the shty steel rims.

couple of problems with the engine but nothing i'd call major..
blew the a$$ out of the LXR muffler - new pop rivets and she's like brand new.
stripped kicker gears - replaced with yx160 gears and seems to be more stable.
shimmed the clutch to reduce vibrations.
snapped timing chain due the the cam retaining plate coming loose, and now i think i have a slight bent inlet valve.. nothing a hammer and valve re-face wouldnt fix, until then its my auto comp lol..

im about to mod the standard clutch basket to run crf50 cush rubbers..got all the parts just need to get off my a$$ and do it lol..

oh and i replaced the oil in my forks with 5W oil to the same height, so much better to jump now..

 

[Carlts]

Hey Sean just a quick question... Im doing very similar build indeed and I was wondering what handlebar you are using. Im getting the DNM hornets and clamps as well so would I need different clamps for the handlebars or are the handlebars 7/8's ?

cheers for the help