430CR 82/83 twinshockracer

[Jens Ries]

this is a report about building up my CR430 for twinshockrace in Germany from last winter. It s allowed to tune up the bike with modern components but you have to use: aircooled engine twinshock or yamaha cantilever for rearwheelsuspension and rightsidedownforks at front .. and of course drumbrakes.

first step was, days and weeks of brainstorming and collecting ideas, then upstairs to my store, collecting parts, then brainstorming again
decission was 430 ' 82 engine, ITC frame from a 250CR '83, marzocchi 45 from a 610TC' 97

 

[troy deck]

get r done dont forget the pics

 

[Jens Ries]

after finding the basics cuted off all unnessesary parts and brackets from frame and swingarm and cleaned the weldinglines.
Then cuted off the mounts for footpegs. Chosed another position, a little bit more back and higher, like at the 250cc worksbike from '82.

 

[oregonsage]

Should be sweet.

 

[Jens Ries]

after fiting the pegs made some brackets for skidplate, sterring damper, pipe and side panels. Closed some open profiles and welded some coils for mounting the gastank

 

[Jens Ries]

after framework began to modify the swingarm. welded a mount for the '85 monoshock chainguide and sheeds for fixing a '85 rearbrakeplate. Changed the connection from pedal to brake from rod to cable and welded a mount for this above the ITC mount

 

[justintendo]

interesting modifications...you have inspired me since i have several spare frames of different years

 

[Jens Ries]

Some years ago I rode a CR 430 '81/'82 . I like the engine, its like a big 250, but the ITC chassis is much better to ride. It s nearly like a modern one. Just the position from footpegs is oldschool.
If You want to modify a frame, use destroyed ones from husky for material like sheets and tubes, because it s the best You can get for this job.
Hard to work with, but very strong.

 

[Jens Ries]

last step was cuting off the weldinlines carefully at the backframe, then lifted the seattubes for 4cm at the back and welded the rods coming from shockmount again
and frame ready for powdercoating

 

[Jens Ries]

fine stuff from good old England, ordered my own x-mas present at hva-factory

 

[suprize]

sweet job. I would have used an 84 frame for better steering? tighter rake. the 83 will be more stable at speed and as its for mx its probly not that big an issue.

will you match the case ports and blank off the crank balance holes?

 

[LtColMXUSMC131]

how do you like their pipes?

 

[Jens Ries]

@ surpize : Didn t know about the difference from 83 to 84. But didn t have the choise, because did only have the 83 CR frame.
but for my next ts racer want to use a WR 400 84/85 frame. How is this about steering and handling? I notice the diff. to CR is the swingarm is an inch shorter.
@ LtColMXUSMC131: the pipe from hva factory GB is for WR 430. It works well from lower rpm (30 years ago I rode a YZ 125 too)

 

[Jens Ries]

to suprize.. didn t match the case ports or modify the crank ... do You have a leading for this, or pics from this? ... I m using a stock crankshaft and housing

 

[suprize]

Hi Jens, the 84 bikes are 1.5 degrees tighter in the stem head angle (experts? is this right?) from what I remember as Husky were refocussing on Europe enduro after years of American desert development (their biggest market). the liquid coolers turn a little easer

to match your ports, place the base gasket on the barrel and remove any excess metal in the transfers to match the gasket outline and smooth it all out then bolt each half case up to the barrel and make sure the transfer casting in the case matches the barrel nicely. see my thread on the 400 rebuild in restorations. some good pics.

Don't get excited and change the port heights in the barrel (especially the exhaust) unless you have factory specs as it can destroy the easy nature of the engine and turn it into a 125 screamer!!

if you shove some cork in the crank balance holes, it increases primary compression and helps a little with response. make sure you seal it with araldite or similar or else it will be hard to get running right!. KTM use an aluminium plug to do this. (I found 1 of mine in the exhaust pipe after it did a circuit of the engine!).

couple of tips to help

 

[Jens Ries]

no I didn t do this all. I m using all in stock conditions. But thanx for the tips .. ll do, when I ll change to next pistonsize.

 

[Jens Ries]

made a seatbracket from aluminum
gastank in oldschool slipoverdesign from sixties

 

[ruwfo]

@ surpize : Didn t know about the difference from 83 to 84. But didn t have the choise, because did only have the 83 CR frame.
but for my next ts racer want to use a WR 400 84/85 frame. How is this about steering and handling? I notice the diff. to CR is the swingarm is an inch shorter.
@ LtColMXUSMC131: the pipe from hva factory GB is for WR 430. It works well from lower rpm (30 years ago I rode a YZ 125 too)

You'd be better off with a 84 250XC frame as it has a aircooled motor like your 83, 84/85 are watercooled & the frame are different.

 

[Jens Ries]

yes the frame I want to use is from a lc one ... what s the difference? steringtubeankle? or wheelbase over all? .. the problem for me is to get a 250 XC frame .. in Germany huskyparts from these days are very rare.

 

[suprize]

there is a few brackets for the radiators and the pipe is slightly different. tank has cut outs for the radiators as well. should be no issue