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    Suggestions for a good handling vintage styled dirtbike?

    It's inevitable that sometime I will end up getting a dirtbike in the next year or two... Wife even wants one now. Just like my GS, I expect a lot... I may borrow or buy my brother's 99 Honda CR125 2 stroke to toy around on, but I'd really like something like my GS - a classic, vintage styled bike that is modified to ride much better than when it rolled off the production line, primarily in suspension and brakes.

    I am trying to track down a Rickman CR frame to build as a GS750 big bore or GS1000/1100/1150, and noted that Rickman got their start making dirt bike racing frames. I see A LOT of Rickman Zundap 125cc frames for sale, although I have no familiarity with Zundap's. an old Suzuki 2 stroke engine would be cool, but a 4 stroke in the 250-450cc single cylinder thumper would probably be more fun, more torque all around, vs a 2 stroke which basically typically just want to run at WOT all the time from the sounds of most dirt bikes my friends have had.

    Is a vintage twin shock frame, even a good one like a Rickman, just going to be obsolete in handling offroad compared to a monoshock? I'm sure a modern fork and brake could swap on pretty well, and I shouldn't have any problem eventually turning up a set of vintage Fox Factory Shox in the dirtbike version with longer travel (match my GS Fox Factory Shox!). I rode BMX for a long time, dirt trails/jumps, skateparks, etc, and Mountain Bike a lot still. I'd imagine I would be running any dirtbike pretty hard. Not looking to do lots of MX jumps, but very much wanting a cool bike to run on National Forest Service roads in the Wayne National Forest near me and Monongahela National Forest in WV, maybe Daniel Boone NF and George Washington-Jefferson NF just across the WV border in VA.

    Tips/Suggestions? The Rickman thing I am kinda hung up on. Fitting a Suzuki engine into the Zundap 125cc frame with a vintage style tank seems like a route I could take... Suzuki DR aluminum swingarm, Fox Factory MX Shox, newer front end.
    '77 GS750 920cc heavily modded
    '97 Kawasaki KDX220R rugged terrain ripper!
    '99 Kawasaki KDX220R​ rebuild in progress
    '79 GS425stock
    PROJECTS:
    '77 Suzuki PE250 woods racer
    '77 GS550 740cc major mods
    '77 GS400 489cc racer build
    '76 Rickman CR1000 GS1000/1100
    '78 GS1000C/1100

    #2
    My dad, amongst all of his other mechanical glorydaze wrenching in faasssstttt GTO's, british sports cars, school bus mechanic, and his own service station, was a pit mechanic in the 70's for a hare scramble racing team running Penton's... The one with the chromoly frame and rare chrome/aluminum tank below sounds/looks awesome!
    From an article on the best and worst vintage dirtbikes:


    SUZUKI: One model stands out, the 1973-74 TM-250 Challenger. Smaller, lighter and nowhere near as violent as the TM-400 (with it's terribly overpowered frame), it had a few handling quirks, but was fast and reliable.
    RM125 - Good 125cc racer that you can get for half the price of an Elsinore. Light, fast, and reliable.


    PENTON: John Penton had KTM build him some great bikes, and the best of these were the 250 and the Mint 400, a 352cc machine that weighed little more than a 250. You could win a vintage race on one of these beauties, and parts are still around.

    1974 PENTON 250cc:
    ******1974 was the first year that Penton produced its 250 model with longer travel front and rear suspension, and frames made from high-grade chrome-moly steel. These engineering advancements combined with engines supplied by KTM made the Pentons a force to be reckoned with on motocross circuits around the world and even today, 40 years later, the name Penton still holds major significance for enduro and motocross riders around the world. http://silodrome.com/penton-250-enduro/


    PENTON 175cc JACKPINER:
    made by KTM for Penton. Eastern woods riders like to collect and restore these bullet-proof little beauties. Don't expect to find the parts as common as with Japanese bikes.


    TRIUMPH:
    Go for it! No question about it, a Triumph is one of life’s true joys. If you haven’t ridden one, then shut up. Forty cubic inches of horsepower is not to be sneezed at. And if you can locate a Rickman Triumph in good shape, don’t buy it. Instead, call me and let me buy it. Many consider these the most beautiful dirt bikes ever built. Yeah!



    UNRESTORED RICKMAN TRIUMPH TR6:


    AWESOME! RICKMAN ZUNDAPP 125cc MODDED WITH TRIUMPH 200cc engine!!!!:
    http://www.framecrafters.net/show-project.php?id=9 These Zundapp 125 Rickman's seem to be the most plentifully available Rickman model on ebay, and could make an awesome basis for a really cool bike with the Zundapp engine, or a bigger 4 stroke thumper, Suzuki TM250 engine, or who knows what else,,,



    RICKMAN ZUNDAPP 125cc




    HONDA CR250 ELSINORE: One of the most popular (and expensive) vintage racers. It was light, fast, and handled well. Parts are still available, but they aren't cheap.




    KAWASAKI: They made a rotary-valved 238cc racer that was a rocket ship (around 1970) that pumped out some outrageous horsepower and gobs of low-end torque. Restore one and holeshots will be yours. There was also a Rickman-framed version of that bike that was a bunch lighter than the stock Kawasaki. Finding one will not be easy, but if you can locate one, go for it.
    The F-81m was a stripped down, modified version of their F-8 enduro model. This was the offering in the 250cc class as pictured below. It sported a rotary valve induction two stroke engine, Hatta forks and shocks, steel gas tank, and aluminium fenders.



    RICKMAN 250 MONTESSA: Spanish engine in a custom built British frame



    HODAKA: Think about a 1973 Combat Wombat or a 1972-73 Super Rat if you want a bike with a huge chromed tank and a lot of personality. Parts are readily available.
    Last edited by Chuck78; 10-03-2015, 08:59 PM.
    '77 GS750 920cc heavily modded
    '97 Kawasaki KDX220R rugged terrain ripper!
    '99 Kawasaki KDX220R​ rebuild in progress
    '79 GS425stock
    PROJECTS:
    '77 Suzuki PE250 woods racer
    '77 GS550 740cc major mods
    '77 GS400 489cc racer build
    '76 Rickman CR1000 GS1000/1100
    '78 GS1000C/1100

    Comment


      #3
      Wow. the Penton 250 with it's cromoly frame seems like a pretty awesome candidate for my style with a 1990's or newer fork and disc brake front end, maybe some newer slightly longer travel shocks...

      The Rickman Zundapp 125 might be in second place... for some reason the Rickman 250 Montessa had a single down tube frame, but the little 125 had a double down tube frame, strange. At any rate, I could see myself getting one of those and heavily modifying it.




      Are there any classic styled dirtbikes that look like these, but are from the early 80's and have a monoshock? Can you tell I am at home nursing a nasty cold and bored?
      Also, any dead realiable Suzuki single cylinder 4 stroke engines that I could shoehorn into that Rickman Zundapp frame?!?
      '77 GS750 920cc heavily modded
      '97 Kawasaki KDX220R rugged terrain ripper!
      '99 Kawasaki KDX220R​ rebuild in progress
      '79 GS425stock
      PROJECTS:
      '77 Suzuki PE250 woods racer
      '77 GS550 740cc major mods
      '77 GS400 489cc racer build
      '76 Rickman CR1000 GS1000/1100
      '78 GS1000C/1100

      Comment


        #4
        Well I'm thinking a 74+ Penton 250 or a pair of Rickman Zundapp's might be the ticket, upgraded modern forks & disc brake front end, upgraded shocks. Might try to stuff a Suzuki DR350 single cylinder 4 stroke engine into 1 of em & keep the other a Zundapp 125cc, as from accounts that I have read, they could out pull some 250's of the their day on hillclimbs. Wiseco makes a bore - in 385cc kit for the dr350, and a $$$$ 440cc kit with a larger sleeve to bore into the block.
        Last edited by Chuck78; 10-04-2015, 11:49 AM.
        '77 GS750 920cc heavily modded
        '97 Kawasaki KDX220R rugged terrain ripper!
        '99 Kawasaki KDX220R​ rebuild in progress
        '79 GS425stock
        PROJECTS:
        '77 Suzuki PE250 woods racer
        '77 GS550 740cc major mods
        '77 GS400 489cc racer build
        '76 Rickman CR1000 GS1000/1100
        '78 GS1000C/1100

        Comment


          #5
          Those bikes are pretty small and compact. I don't think you could find a OHC single of any size to fit in those frames.

          I've seen some Pentons and Rickmans lately. Nice bikes


          The Kawasaki goes for 5 figures, in case you thought the Elsinore is spendy
          1978 GS 1000 (since new)
          1979 GS 1000 (The Fridge, superbike replica project)
          1978 GS 1000 (parts)
          1981 GS 850 (anyone want a project?)
          1981 GPZ 550 (backroad screamer)
          1970 450 Mk IIID (THUMP!)
          2007 DRz 400S
          1999 ATK 490ES
          1994 DR 350SES

          Comment


            #6
            Good to know. Sounds like the Zundapp 125cc can be modded a bit to be more competitive with newer bikes of the same size range. Might keep an eye out for one of those. Especially since I am pretty close to having the finances to pull the trigger on a neglected old Rickman CR750 frame/chassis that has been modded to fit a GS1100E engine. Deciding factor aside from having enough cash was my buddy last night telling me some oncoming left turning car cut him off in his 86 Ninja and he crashed into them and folded his forks and went airborne. The Rickman CR frame has early ninja/GPz forks on it that are of no use to me. If I get one Rickman, why not a 2nd?!? and a 3rd!?! a pair of Zundapp Ricky's for the wife and I!

            My buddy ahs a DR350 Suzuki so I could compare the engine to the Ricky frame. There is a bare RIckman Zundapp frame for $185 shipped on ebay now... Although my buddy with the DR350 asked why in the heck I would want to take an awesome vintage 2 sroke out and put in a modern 4 stroke!? More torque by far, don't have to run it full throttle all the time like 2 strokes like to run, can make it a big bore 385cc air/oil cooled brutally reliable engine as DR's are known for. IF it would fit. Hydrauic Disc brake wheels and modern fork are the primary upgrades I'd be looking for on any vintage dirtbike. At least disc front.

            The bigger question is - should I stuff an 82-86 GS1100/1150 engine into the Rickman CR frame for the ultimate in vintage bike power to go with the ultimate road race twin shock chassis? Or should I settle for a standard big bore GS750 with head work and higher lift cams? I can get 798cc 11:1 pistons and rings NOS for $250, Wiseco 844cc with head gasket for $500 or less, JE Pistons custom 894cc (into 850 jugs) or 1023cc (into resleeved 850 cylinders) for about $680. I think the 750 based engines with bigger pistons and cams would be more than fast enough to impress anyone and get me into a lot of trouble, and stick with a kickstarter bottom end as I prefer, but the sheer power and awesomeness of the TSCC GS1100/1150's is a shoe-in for this ultimate vintage aftermarket frame...
            '77 GS750 920cc heavily modded
            '97 Kawasaki KDX220R rugged terrain ripper!
            '99 Kawasaki KDX220R​ rebuild in progress
            '79 GS425stock
            PROJECTS:
            '77 Suzuki PE250 woods racer
            '77 GS550 740cc major mods
            '77 GS400 489cc racer build
            '76 Rickman CR1000 GS1000/1100
            '78 GS1000C/1100

            Comment


              #7
              A bit of a late update... but I caved in for this beautiful 1974 Rickman 250 VR (Montesa 73M "Vehkonen Replica" 250cc beast of a piston-port 2 stroke engine). I saw it here in the picture at AMA Vintage Motorcycle Days in July, but didn't hook up with the owner for a few months.


              I committed to buy it before I had really done real trail riding. We are VERY LUCKY to have 4 different ATV trail networks in the Appalachian hills of southeast Ohio in Wayne National Forest, & the largest of the 4 systems (75 miles of very well maintained but very rugged & awesome trails) is just 1 hour from us. After riding that very frequently on my more modern beater trail bike that I also just got in 2016 (Kawasaki KDX200/220's RULE for woods riding! Great bike on.great trails is extremely addicting!!!), I realized that a vintage '74 & earlier motocross suspension really wasn't going to cut it on a whole lot of those trails, much more suspension travel was a MUST to ride there without getting beat up and bounced off the trail...
              I then thought I'd do a few upgrades to make the little Rickman chassis suitable for my wife to ride on the smoother/easier trails & planned on getting the ultimate in vintage long travel suspension Enduro/Woods bikes, a Suzuki PE175, to have a vintage machine with 9" suspension travel that with better shocks could handle any terrain. 1975+ was the era referred to as post-vintage/evolution in motocross chassis / suspension technology.... everything got long travel off road suspension vs 74& earlier which aside from 74 Pentons and Curnutt shocks was all street bike suspension with softer springs and off road damping.


              Well if you know me, you know I can't leave anything alone... I had a vintage suspension guru buddy set me up with a pair of longer travel taller Fox Gas Shox set up specifically for this Rickman, so now the rear end has gone from 3.5" wheel travel with antiquated super soft Girling 12-1/2" shocks to 5" rear wheel travel 13-3/8" Fox's... HUGE upgrade. Feels great to have proper spring rates and longer travel on it!



              Kenny also sent me a pair of Betor fork 35mm long travel (8") damper rods to go with it, & is sending me some black 1977-ish Betor 35mm fork sliders to go with the long travel damper rods. Pretty good setup for upgrading a pre-74 mx machine! The 8" travel Betor stuff will just swap straight on in place of the stock 6" travel stuff. Heck, Racetech even makes a fancy upgrade kit with an add on upgrade piston/piston ring, and Racetech Gold valves! That is definitely in the future for this thing. Kenny also told me of a trick to add 3/4" more travel to them...



              I'm adding a Neutech TüBliss system to this bike, & a Kenda Equilibrium trials/trails hybrid tire that is taller and with more knobs to give the ultimate grip in all but deep mud. Instead of standard 12psi, you can now run down to 3-4psi for extreme traction when needed, no worries of pinch flats, & the Tubliss 100 psi inner rim lock tube chamber protects from dinging the rim. This also will be a huge gain on this 5" travel suspension by adding more suspension travel in the way of tire squish at around 8psi that I plan to run.

              Even further, I was looking at swapping an aluminum PE175 Suzuki swingarm to it in order to move the axle rearward from the shocks to gain even more travel. Also considered getting a Rickman 125 swingarm and just extending it (2.5") and bracing it in a way to lay the shocks down at an angle to gain more rear travel in addition to the 3/4" travel gain from the 2.5" extension... add 1" longer lower shock eyes to the Fox's to make up for the lay down angle and extension if I go that route...

              All of this travel on a vintage engine with the countershaft sprocket so far forward of the swingarm pivot means a wide range of chain tensions throughout the travel, so additional chain guides/rollers will be needed. A lot of work but this thing is slated to be the best enduro equipped Rickman dirt bike out there once In done with it! And these Rickman mx's are undoubtedly some of the most beautiful vintage mx machines ever made... Around 8.75" travel front and rear, huge shock/fork valving upgrades, & TüBliss...

              The VR250 engine is a beast for its age, great power off the line, revs to 10,000rpm... previous owner said it was one heck of a hill climber. A tiny chassis 193lb mx bike with a torque monster 33hp 2 stroke screamer. Montesa VR250 engines got the nickname "Montesticle" because they had so much balls...

              Check this out:
              "the VR250 was one of the great piston-port engines; having one of the few 1973 VRs that Montesa imported was like cheating that year. It was an embarrassing engine to have in 1974 because if you didn't get the holeshot, everyone knew whose fault it was."
              "the engine did definitely come on the pipe with some hit in the lower midrange.
              My brother barely raced his & admitted he was afraid of how quick it was, had trouble committing like he needed to for holeshots"
              Last edited by Chuck78; 11-24-2016, 11:10 PM.
              '77 GS750 920cc heavily modded
              '97 Kawasaki KDX220R rugged terrain ripper!
              '99 Kawasaki KDX220R​ rebuild in progress
              '79 GS425stock
              PROJECTS:
              '77 Suzuki PE250 woods racer
              '77 GS550 740cc major mods
              '77 GS400 489cc racer build
              '76 Rickman CR1000 GS1000/1100
              '78 GS1000C/1100

              Comment


                #8
                Here's the fairly modern trail ruler that I picked up, 1999 Kawasaki KDX220 - 36hp & 211lbs after ditching the tanker stock exhaust for an FMF Gnarly Desert Race pipe... A buddy showed me a link to this but I blew it off. Then Kenny my vintage enduro racer/vintsge suspension restoration buddy talked them up to me.
                Me at Wayne National Forest at my favorite trail area, the Dorr Run Loop and the other 7 or so loop systems within the outer Dorr Loop:


                Really what it came down to was the fact that many 2 stroke woods/enduro bikes do in fact make low end torque similar to 4 strokes, as it's all dependent on the intake & exhaust port configurations in the cylinder as well as the exhaust expansion chamber design. Both of those dictate the engine power carachteristics the same as camshafts on 4 strokes. These 2 stroke enduro engines stoll act like 2 strokes but with a more mild powerband "hit" (aka when they "come on the pipe" - when the volume of exhaust gasses pressurized the exhaust pipe's expansion chamber at its peak power design point) when you get up to the sweet spot in the rev range.

                Early water cooled 1990's KDX200:

                My brother's2000 Honda CR125 is heavily modified & is an absolute 2 stroke mx missile, but the bike has very little low rpm power, and then when it gets to the right spot in the rev range snd gets "on the pipe," the thing just explodes with power enough to very rapidly loft the front wheel in the air and send the bike rapidly forward with any unsuspecting riders getting ejected rapidly off the back of the seat... it's as is someone poured a bottle of Nitrous Oxide down the carb...

                1980's air cooled KDX200 (I'm lusting after an 86-88, first years of power valve exhaust port system to build more torque at low rpm by de-restrictions the port size only after hitting higher rpm, last years of air cooled):


                After really learning more about the Enduro 2 stroke engines, the real deciding factor was the massive power to weight ratio advantage of 2 strokes. A 95-06 KDX200 (or 97-04? KDX220 - built for even more low end torque for tighter/steeper terrain woods riding) weighs substantially less than a 200 or 250cc 4 stroke and makes the power of a 350-450cc 4 stroke... the KTM EX-C & XC-W 200/250/300's are basically the same bike as these Kawasaki KDX's, & are in the opinion of many, some of the best trail riding enduro bikes one can buy on a budget. Or break the bank on if you buy a brand new KTM, as they still make these but Kaw pulled the plug in 06 when they shifted mostly to 4 strokes.
                Husqvarna, OSSA, & a few other European brands make similar modern 2 stroke enduro models, but the closest thing the Japanese manufacturers offer is the Yamaha YZ250 motocrosser, the most popular 2 stroke mx racer to convert to a woods/enduro bike due to light weight and ample low end power. 2006+ has the SSS (Speed Sensitive Suspension) setup that can be dialed in fir more plush enduro settings with the click of a dial, & all you need to do is add a weighted flywheel to aid in more low end torque and stalling resistance, & add an aftermarket pipe to focus the powerband more on low end for those technical sections and hill climbs right out of tight turns.
                Last edited by Chuck78; 12-03-2018, 09:02 AM.
                '77 GS750 920cc heavily modded
                '97 Kawasaki KDX220R rugged terrain ripper!
                '99 Kawasaki KDX220R​ rebuild in progress
                '79 GS425stock
                PROJECTS:
                '77 Suzuki PE250 woods racer
                '77 GS550 740cc major mods
                '77 GS400 489cc racer build
                '76 Rickman CR1000 GS1000/1100
                '78 GS1000C/1100

                Comment


                  #9
                  I actually just had a really dirt cheap deal on a 70's Suzuki PE250 just fall right in my lap, but not sure if I want the beastly engine's 246lb weight vs the lighter more agile PE175's 216lbs weight.



                  A few hundred bucks for a PE250 that was my buddy's father in laws, but hasn't been started since his battle with cancer began 15 years ago. It's pretty rough cosmetically, but these are tough bikes. OEM parts & aftermarket support are still very readily available, & these bikes are highly capable with just a simple rear shock upgrade and a freshening up on maintenance. Hmmm.....
                  Could eventually trade for a PE175 if the weight still bothered me:
                  Last edited by Chuck78; 11-25-2016, 11:31 AM.
                  '77 GS750 920cc heavily modded
                  '97 Kawasaki KDX220R rugged terrain ripper!
                  '99 Kawasaki KDX220R​ rebuild in progress
                  '79 GS425stock
                  PROJECTS:
                  '77 Suzuki PE250 woods racer
                  '77 GS550 740cc major mods
                  '77 GS400 489cc racer build
                  '76 Rickman CR1000 GS1000/1100
                  '78 GS1000C/1100

                  Comment


                    #10





                    Had a second old neglected '77 PE250B deal confront me...Couldn't pass this one up! The '77 PE250 with its 1-year-only aluminum tank, minimalistic old school looking handlebar number plate, & 77-only pattern on the headlight gaurd is definitely in my opinion the best looking of the PE's.
                    Its a bit of a basket case that hasn't been ridden in 25+ yrs but it is titled (must-have for riding all the public lands trails here in state and national forests) and came with a large lot of spare parts, 2 extra engines, 2 new Wiseco pistons, etc.
                    I have a spare cylinder here with it that has engraved "ported by Tom Turner's 2-Stroke Racing" & a phone number. Let me tell you, these ports look very impressively reworked! I'm almost afraid of how much power the Wiseco + legendary Tom Turner porting job will produce! He was truly a 2 stroke tuner/builder legend... I think I'll send this cylinder off to PowerSealUSA to have it bored for the 68mm pistons and then specially Nikasil plated to preserve the bore so that the cylinder porting never has to be re-matched onto a new sleeve

                    The 80-81 PE175 was really what I was after, & the full floater rear end 82-84 pe175 would be hands down the best handling of all PE's, but the classic look and twin shocks and alloy tank swayed me to the 250. Well, the power potential did have a bit to do with it as well!
                    Last edited by Chuck78; 06-03-2017, 10:23 AM.
                    '77 GS750 920cc heavily modded
                    '97 Kawasaki KDX220R rugged terrain ripper!
                    '99 Kawasaki KDX220R​ rebuild in progress
                    '79 GS425stock
                    PROJECTS:
                    '77 Suzuki PE250 woods racer
                    '77 GS550 740cc major mods
                    '77 GS400 489cc racer build
                    '76 Rickman CR1000 GS1000/1100
                    '78 GS1000C/1100

                    Comment


                      #11
                      The PE250 forks are only 36mm, but to avoid issues with adding substantial suspension travel / steering stop mods, for now I'm upgrading the rusty 7.6" travel 77 PE250 forks to an 82-83 pair of DR250 forks that will be a direct bolt on - same triples, axle, & drum brake plate interface. The 82+ forks use replaceable lower DU bushings on the stanchions vs the older forks, & are longer travel at 9.6" - which I will have to reduce 1/4" or so ( to keep the tire from coming to a screeching halt when it contacts the fender!) and also slide the triples down over the forks to keep my steering geometry good - shooting for quicker turning than stock.
                      Rear is getting my 4th pair of Fox Factory Shocks which I had 1 lonely remote reservoir shock for parts, bent shafts and rusty. A vintage suspension restoration buddy of mine happened to have a nearly identical shock missing its mate also, so he is restoring those for this PE for me!

                      Going from 14.25" stock / 7.8" travel to either 14.875" shock / 9.44" travel or 15" shock / 9.76" travel. And a better chain tensioner to deal with all the added travel which will create more variance in chain tension.
                      Thus thing should be a real trail boss for a vintage bike. I'll see how I like the 36mm forks fir this season. Next year I may have to go on a search for some 38mm-43mm forks 34.5"-35.5" tall. Most early 1980's forks that jumped up in size also got much longer travel, so that's the challenge. Reducing travel 2" on a set of 43mm forks will still leave me with 2" of extra stanchion weight slid into the forks! Trying to drop weight not add. 38mm 82 RM250 front forks will still need travel reduced a lot but are the top pick so far. May have to go non-Suzuki to get something 40mm/41mm and around 35" axle to top.
                      '77 GS750 920cc heavily modded
                      '97 Kawasaki KDX220R rugged terrain ripper!
                      '99 Kawasaki KDX220R​ rebuild in progress
                      '79 GS425stock
                      PROJECTS:
                      '77 Suzuki PE250 woods racer
                      '77 GS550 740cc major mods
                      '77 GS400 489cc racer build
                      '76 Rickman CR1000 GS1000/1100
                      '78 GS1000C/1100

                      Comment


                        #12
                        The PE250 actually has the largest drum brakes of any Suzuki off road bike of the era, 150x28... AND if I could only ever find an 82-85 GN250 street bike, a GS derivative of sorts running a single cylinder DR250 engine, the twin leading shoe front drum brake is also a 150x28 and nearly a direct bokt-in on a PE hub - same axle size! That gets it up to almost disc brake stopping power! I use the rear brake mostly off road anyway (i.e. abuse the rear tire both stopping and accelerating!), & I have a slight phobia of excessive front braking on loose surfaces after spilling the GS750 on a little patch of cinders that I missed recognizing...
                        If swapping forks, the bigger forks have a 15mm axle, and the 83&84 RM250 use 43mm forks and a twin leading shoe 130x22 brake... not as good as the PE/GN hybrid but is an option.

                        If I discard the retro-mod front drum brake look, I can run a late model DRZ250 Suzuki 43mm cartridge disc brake front end with 10" of travel (slightly reduce that) but then it won't be 100% a true vintage ripper... but it will be a really great trail bike at that.
                        Once I determine if the 36mm fork flex is not way too much vs my KDX220's modern cartridge forks, I will be doing full racetech guts in the DR250Z 36mm KYB's.

                        Previous owner had this PE for 25+ years but just got it running last year (new top end overbore/piston) & said he heard a noisey bottom end bearing and shut it down. So I get to split the cases and give er a full going over...new crank and tranny bearings and full inspection.
                        I think I'll put together the one with whichever crank has the least wear on the crank big end rod bearings/crank pin, as-is but new outer crank bearings, so that I can get it going sooner and not have to send the crank to Pearson Racing for a rebuild & truing. Then when I get the ported cylinder nikasil plated, get the other crank rebuilt with a new pin and new connecting rod, fresh bearings /thrust washers everywhere, and build the spare engine with the ported cylinder and fresh crank. Always good to have a spare engine! Especially when I can pick them up with one hand & can swap em in 30 minutes!
                        Last edited by Chuck78; 06-03-2017, 11:10 AM.
                        '77 GS750 920cc heavily modded
                        '97 Kawasaki KDX220R rugged terrain ripper!
                        '99 Kawasaki KDX220R​ rebuild in progress
                        '79 GS425stock
                        PROJECTS:
                        '77 Suzuki PE250 woods racer
                        '77 GS550 740cc major mods
                        '77 GS400 489cc racer build
                        '76 Rickman CR1000 GS1000/1100
                        '78 GS1000C/1100

                        Comment


                          #13
                          My first dirtbike was the Rickman 125 ...and my buddy had a Hodaka Combat Wombat...while the Rickman was nice,it was also flawed with extremely poor shifting(false neutrals way too often) and a few other annoying quirks...my bud's Hodaka was way better motor,handling,suspension,reliability...just not as purty as the Rickman

                          Comment


                            #14
                            Yes, both are the reasons why I got the Spanish Montesa engine'd 250cc Rickman instead! Very beautiful bike, very awesome engine, does not have the shifting problems of the German Zundapp engine!
                            '77 GS750 920cc heavily modded
                            '97 Kawasaki KDX220R rugged terrain ripper!
                            '99 Kawasaki KDX220R​ rebuild in progress
                            '79 GS425stock
                            PROJECTS:
                            '77 Suzuki PE250 woods racer
                            '77 GS550 740cc major mods
                            '77 GS400 489cc racer build
                            '76 Rickman CR1000 GS1000/1100
                            '78 GS1000C/1100

                            Comment


                              #15
                              that is a very kewl bike

                              Comment

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