Author Topic: 1979 RM80N Roach  (Read 35057 times)

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Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #30 on: November 16, 2014, 06:54:12 pm »
Thanks Smed.. i did bake them last week.  Waited till everyone was out then oven roasted them at 100-150 C until i smoked the house out.  Made sure i opened all the windows and then afterwards went around with airfreshner... no one was any the wiser and i think i cured everything up nicely.  The hubs are epoxy so they are slow curing over a period of a month or so. 

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #31 on: November 28, 2014, 10:09:18 pm »
Ok, time for some updates.......

Well, i received the spoke sets from TC Vintage_001 from Ebay in Thailand.  They are great.  He didnt have any for the N,T,X models so i sent him some samples and he made me up a free set for the front and rear.  The bend, length, gauge etc are great and the quality looks good.  Worth a go if you need spoke kits and they are cheap to buy.
Anyway, thought i would put up a review of how i rebuilt the wheels.  I tore them apart, blasted and repainted the hubs, fitted new wheel bearings and new brake shoes.  The brake arms were newly zinc coated and new seals fitted.  Original rims were cleaned up as best as i could and the spoke sets organized.
OK.. here we go.......

This is the front wheel and you follow the same routine for the rear also.  There are only 2 different spokes for the front.  18 spokes with a slightly less than 90 degree bend at the nipple end and 18 with a 90 degree bend.  I did the outside to inside spokes first.  I cant remember which bend it is but just try one of each and you will notice that one bend of spoke will not bend in toward the rim.  Find which bend fits and then just insert them every second hole in the hub.  There are 4 different hole types in the rim.  Find the hole type that corresponds to the direction of the spoke.  Be careful here because i got it wrong once even though i could of swore i was correct.  Anyway, the hole you want leans out to the outside of the hub and in the direction of the spoke.  The other 3 holes either point towards the other side of the hub or in another direction....


Put all 9 spokes in and loosely put a nipple on each one.....


Turn the whole thing over and put the other 9 outside to inside spokes in.  The reason we are doing all the outside to inside spokes first is because we are going to put our inside to outside spokes in last and dont want to get trapped like i did the first time i did it.


OK, we should have all our outside to inside spokes in with loose nipples.  Next, you will use the other bend spokes and go inside to outside.  Work you way around and find the corresponding hole in the rim.


You should end up with something like the above....


Keep the rim on the edge of a table and thread through all the inside to outside spokes as above.....


You will notice that the spokes go over the first sets you put in.  Makes them easy to fit eh.....


The finished product.  Its all loose and wobbly but thats the next bit we will tackle....


I made my own wheel truer using some good ole wood from Bunnings.  A cable tie under the rim and one on the side cut so that they just touch the side and underneath of rim.  There are plenty of Youtube vids to show you various techniques to true a rim so do a bit of research.  I kind of got the vertical runout nice by using the technique of pulling the top spokes up a bit if the rim hit the cable tie at the bottom.  Same for the sides.  If the rim touched the cable tie on the left, i would tighten up a few spokes on the right to pull it over.  Play with it for a while and it all comes good.  Then just nip them all up to your desired tune... i have always tapped them to get a nice high note and check for tightness.

Anyway, thats the basics... just check a few vids out first.  Also, take plenty of pics of your rims before you start so you can see your pattern.  Not all spoke lengths are equal either and also not all rims and hubs are equal on both sides so measure the run out on each side before you start using a straight edge.
Cheers,
Alex


Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #32 on: November 28, 2014, 10:24:28 pm »
Some people will change tyres themselves but wont respoke rims.  I am the opposite.  If i change a tyre, i generally *uck the bead of the tyre, puncture the tube, scratch the rim and bruise my knuckles.  I took the wheels and tyres to the bike shop and let them fit new rim tapes, inner tubes and get the tyres on properly.  $50 all up and i saved myself a nightmare. 
I came home and fitted up the new wheel sets.  Had a few dramas with the new brake shoe springs being too big on the rear and getting caught on the bearing part of the hub.  All sorted by using the old springs that i also had zinc coated.
Below are some pics of the rolling chassis.  The suspension feels great.  Really nice and balanced and lightly damped and sprung both ends.







On a side note... i have a new front mudguard that i was going to fit.  It is a brand new OEM RM80N one but also fitted other models such as the RM60 etc and some TS models i think.  Anyway i unwrap it and its f*cking silver.  Whaaat, seems like the only ones left after 35 years are some from a TS or something that was silver.  Well, these are hard to get and its the correct fit, shape and factory original so i PM'd RedAlert and he said this silver thing is common.  He has my paint mixed for the B and N tanks and said he had enough for the front mudguard.  So i will take it up to Rod for painting... thanks Rod...

Cheers,

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #33 on: November 28, 2014, 10:38:20 pm »
At great expense, i purchased a Cycle Magazine from November 1979 with a shootout of the RM80N, YZ80F and KX80.  I have made a backup of the RM80N part of the test and have posted it up here for educational purposes...  Of note is the fact that the RM was 3 horses down on the Yamaha.  Suzuki gained some power from revised cylinder porting but lost it in the jetting and revised exhaust which has an inside skin with perforations and packing.  The remedy is to get a C pipe which didnt have the power robbing dual layer pipe.  However, they say the RM had better suspension.  I loved the suspension on my YZ80F back in the day so the RM must of been pretty good.
Below is the backup copy of the RM80N test posted up for educational purposes ;-)







Cheers,
Alex

Simo63

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Re: 1979 RM80N Roach
« Reply #34 on: November 28, 2014, 11:01:22 pm »
On a side note... i have a new front mudguard that i was going to fit.  It is a brand new OEM RM80N one but also fitted other models such as the RM60 etc and some TS models i think.  Anyway i unwrap it and its f*cking silver.  Whaaat, seems like the only ones left after 35 years are some from a TS or something that was silver.  Well, these are hard to get and its the correct fit, shape and factory original so i PM'd RedAlert and he said this silver thing is common.  He has my paint mixed for the B and N tanks and said he had enough for the front mudguard.  So i will take it up to Rod for painting... thanks Rod...
Cheers,

No don't do that just yet Alex. First you should try hitting the silver paint with some thinners. You will most likely find the silver is painted on over the original yellow plastic as I have seen this on plenty of NOS Suzuki plastics.  just be careful with the thinners and try in a spot you won't see just to make sure.

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #35 on: November 28, 2014, 11:21:01 pm »
Thanks Simo, i will duck out to the shed and give it a try and report back on the results
Cheers,
Edit: I ducked out to the shed and the plastic is off white underneath... oh well....
« Last Edit: November 28, 2014, 11:27:00 pm by alexbrown64 »

Offline Rossvickicampbell

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Re: 1979 RM80N Roach
« Reply #36 on: November 29, 2014, 12:27:46 am »
similarly to what Simo was saying - Suzuki had some strange bits and pieces NOS/OEM - I have heard of guards etc being silver from the factory regardless of model.
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Simo63

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Re: 1979 RM80N Roach
« Reply #37 on: November 29, 2014, 01:03:02 am »
Edit: I ducked out to the shed and the plastic is off white underneath... oh well....

Oh bugger .. not heard of off-white underneath before?  Oh well off to the painter  ;)

Offline malcolm1

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Re: 1979 RM80N Roach
« Reply #38 on: December 17, 2014, 02:08:59 pm »
Hi Alex, great work. I know how you feel about a bike turning up that doesn't quite 'match' the online pics prior to purchase. I was sent pics of a pristine RM125B but alas, when it arrived it needed quite a bit of work. My RM80B is all original except for pipe and it has the N model pipe - I wondered why it doesn't have that crisp 'crackling' exhaust sound of the B I remembered - hence I've just bought an original OEM B pipe to replace pronto!  8) In late 1979 I'd saved for months and with help from my parents bought me an XR80R as the Honda/Suzuki dealership had just sold it's last RM80N and the new XR80 1980 model was on showroom floor - what a regret! Will start looking for an N to buy cheers Mal

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #39 on: December 17, 2014, 05:45:25 pm »
Thanks Mal, yeh back when i was a kid it was all YZ,s. The 125 B's are a really nice bike.   My 80B is just about finished and only needs the tank which is getting finished off now.  The N is almost there as well.  I just got the crank back from Witch Cycles Suzuki and they installed new rod and shims plus i got a rebore on the barrel and new 2mm oversize Wiseco piston and rings.  Ive put it all back together twice this week.  The reason being that my photos of pulling the engine apart didnt match the pictures in the manual.  He had the primary drive and idle gears on back to front and the thrust washer missing from behind the clutch basket.  Also, there is a spacer that goes on the crank that fills the gap between the crank and seal.  I didnt remember putting the spacer on so i pulled it all apart again and there it was... it was jammed on the crank the whole time.  Anyway, engine is together and back in bike.  Ordered the thrust washer and a few other knickers knackers and then just waiting on the tank and front guard to get finished off. 
Until i read the shootout on the N, i didnt realize there was a difference in the exhaust either.  I have a YouTube vid of the B being revved up and its loud.  You should put up a few pics of the B in this thread or in the B thread i made... be good to compare notes.  Good luck with the N, they do come up once in a while and they are fun to build up.
Cheers,
Alex

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #40 on: December 17, 2014, 06:27:28 pm »
I purchased a copy of Cycle World from November 1979.  It has a mini bike shootout and i have uploaded here for a backup and for educational purposes. 









Cheers,
Alex

Offline alexbrown64

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Re: 1979 RM80N Roach
« Reply #41 on: December 17, 2014, 06:29:35 pm »
And here is a pic of the latest update to the RM80N.  Still needs some work but were getting there now....



Cheers,
Alex

Offline Richo52

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Re: 1979 RM80N Roach
« Reply #42 on: December 17, 2014, 09:08:52 pm »
Absolutely fantastic job Alex ........lets do the 79 Wanneroo state round again!
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Offline malcolm1

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Re: 1979 RM80N Roach
« Reply #43 on: December 18, 2014, 09:52:26 am »
Hi Alex, took some pics of my RM125B and 100% original CR125RZ (like your B it has everything original and in great condition incl tyres and sprockets etc) - I'm actually having trouble uploading the pics here - isn't it simply using the insert image button? My second 125B is a bit rough and needs work. I don't have the home workshop and time atm so thinking of sending it away to a dealership or find a restoration workshop to give it a bit of spit and polish - just enough to take out on weekends. Looking forward to seeing the bikes once the tanks are on - fantastic job!

Offline FourstrokeForever

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Re: 1979 RM80N Roach
« Reply #44 on: December 18, 2014, 10:40:49 am »
Top work Alex. The bike looks a million bucks.
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