Batavus Moped Manual

  1. Batavus Moped Repair Manual
  2. Batavus Moped Parts
Trike

Serving the Moped Community on the Web Since 1997. Batavus service manual. Batavus M48 ignition (3 Subcategories) batavus M48 clutch parts.

  • Batavus HS 50 Moped. Need a manual for your Batavus HS 50 Moped? Below you can view and download the PDF manual for free. There are also frequently asked questions, a product rating and feedback from users to enable you to optimally use your product.
  • Batavus moped digital workshop repair manual 1976-1978 download now Batavus Moped Complete Workshop Service Repair Manual 1976 1977 1978 Download Now Factory Service Manuals.


It runs and works good. thanks -- Magty99 at aol.com. The HS-50 was also available in a deluxe model which included directional signal lights (indicators). The motor turns and its not seized. 1974 Batavus Deluxe Model, Dual Fuel Tanks, 50cc 30mph, Moped, vintage 2 stroke, Made in Netherlands, all European components, strong engine, runs, rare! Think it might be TS 50, early 60's. Pretty cool find but very hard to find any info on it. Stroud glos, Wed Feb 16 2011 What is its value? -- Stijn Mertens -- stijn.mertens at hi.nl, June 26, 2001 starts right up and runs great. Hello.would you send me some pictures about BATAVUS, BILONET.COMBISPORT, year 1962 or 1963 -- EDWARD-COOLS -- MECHELTJE at hetnet.nl, July 16, 2000
Mopeds were something new in Indianapolis. NH, USA.
Hi i own a Batavus moped and it looks like a VA. now i have a repair book but itson a 76 hs 50 and so much is different. If so, how much? cdsk9 at mchsidot com
'normal' or 'fast' engine? please read the description carefully and study the pictures. It ran in April 2017 and has sat since.May need somectlc or light carb clean.My friends brother passed away and this was left behind.Always garaged. Featured Products.
It runs and is in good condition. -- Robbie -- rmnicholson at earthlink.net, February 4, 2000 anything? She definitely needs work yet she’s not running now. I have spent hours on the internet looking for a picture of the first bike i ever had which was a Batavus pronto 49cc i don't know the year. Vintage Batavus Mo Bat moped. There is one on Ebay I have 1979 Batavus Regency,48cc, Three Wheeler.Is this a production model ?
I was given a black Batavus Bingo (1977). independence mo usa, Thu Dec 21 2006 What do these characters mean? The guy is looking for a good Batavus, he is willing to pay good money for it. I am sanding the rust off and hope to get it running, if you have a manual of I just cant wait to get this beauty on the road. madasafishdot com, June 20, 2000 Good machine to rebuild or used for parts. -- best regards -- Jaap Niemans --nidoz at zeelandnet.nl, September 06, 2000 subject: BATAVUS DUTCH Wheels go for like 80 bucks a piece on eBay so parting it. Wed, 09 Feb 2005
Sometimes you have a vision for a moped and sometimes you execute on that vision. Thanks very much for your help. I've heard I could modify to fit almost any engine but in reality I would prefer to keep it original if possible , any help would be niceEverett, Mass, USA, Sat Aug 01 2015erudolf64 at hotmail.comwanted info or parts1961 batavus ts 50 super sportwanted info,wiring diagram for jlo german engine,or parts. Excellent Condition. RE: BATAVUS STARFLITE parts Thank you. london ont, Thu May 04 2006 It appears to be CHERRY. The Batavus Mondial is one of the few Batavus mopeds that didn't come with a Laura moped engine. Hi I am in need of a muffler that will fit the Batavus mopeds 48cc. HS50 Batavus. translation.
Batavus VA 50 Moped / Scooter.
Is there a dealer in the Virginia area USA? The HS50 is a motorcycle style moped built to the specification of the British Batavus importers, Harglo Ltd. Like the other Laura engined models, the HS50 has single-speed transmission with automatic clutch and can reach a top speed of 35mph. i need a carburator as soon as possible
Thanks in advance! Email: Louscanoes1 at aol.com just had it serviced and its 100% ready to go. Rick M. OCEAN CITY, MARYLAND USA. Shop with confidence. I'd trail my friends all over on it. installed.
suggestions where we can find them???
1976 Batavus MopedPurple. know is that they are made in Holland and Batavus only makes bikes know. Contact one of the moped dealers and specify the parts you require. Should I restore it and sell it, sell it as is, or restore it and keep it? One flywheel cover missing,Are they the same? nanbeek at homedot com I've restored it completely but I just need a few things. Runs great.
frederick, md, Tue Jul 19 2011 think they can run both.
I'm looking for parts and info for a tricycle batavus. I will gladly pay a good price even for a functional used part. Batavus also continuously develops smart and useful technical innovations that make cycling safer and more comfortable. It's super hard trying to match it at the hardware, or small engine shop.... Great shape. I own a 1979 Batavus Regency HS moped. OCEAN CITY, MARYLAND USA. 1974 bingo batavus
need help parts I would like to know what the plug gap and point gap is for this relic, the moped was given to me by a neighbor, it runs but it spits and sputters, any help on this scooter is appreciated, thank you for your time, manual lists dealer in Ga., USA... still looking for info...built in Holland. Durolon Batavus
I put a lot of work into it, and did a lot of research on it. Batavus 1978 Starlite Batavus I'm pretty sure that once it catches it will burn off any varnish or carbon and run well after that. batavus 1979 regency parts Hi They produced special models for USA,so type-names like 'Regence' and so can't help...I never seen one in Holland. Ontario Canada, Sat Oct 10 2009 batavus 1975 starflite - tramp It is ribbed on the inside and it connects the pedals to the motor as needed for starting. Batavus ?? rhode island, usa, Mon Aug 18 2008 batavus mk4s
naturalway at mindspringdot com moped part Login. Frank, I live in Boston , MA -- frfrank at goarch.org, March 8, 2002 I have a Batavus that is missing a motor it is red, white, swooping wide front fender, on the tank it has trophies and big badges on the side.
I am going to try to restore it, can anyone help me? batavus supersport appelbloesem ! It was manufactured from 1975 to 1979 (maybe longer). budiswasonoyahoodot com Batavus Mopeds 1979's Thanks so much.TeresaFall river Canada, Thank you,SteveWindsor, Ontario, CanadaEnglish. bactavus start but dies Should you discover more which could help others please share. thanks hlland/millingen aan de rijn You may have a look at www.batavusbromfietsclub.nl, Tue Aug 21 2007 ROn -- vinylhut at shianet.org, December 25, 2001 Batavus ‘mother bike’ (also for pregnant women). -- jhathaway9 at pridigy.net, August 17, 2000 -- hairymoped at msndot com, October 2, 2002 cedar key, fl, Tue Aug 06 2013 Batavus 50 moped value batavus CO, Thu Apr 15 2010 to batavus m48 egine?? New listings: Vintage Batavus Mo Bat moped - $750 (Point pleasant), 1974 Batavus 50cc Moped vintage 2stroke strong engine rare Made Europe - … I need a clutch pack for '80 moped
Mondial models came with the variated Peugeot 103 engine. -- Jason, NY -- Aero754 at aoldot com, June 5, 2000 batavus moped 48 cc year 1976 Batavus manufacture ceased around 1983. Any ideas?. appreciated. -- Peter Cain -- louise-paddy at Hello, Guest!
Batavus Parts
They are telling me that I have to tag the moped to ride in on the street. At the grand old age of 46, I'm trying to find any pictures, In budi from Indonesia. cruzinglo at hotmaildot com Wher do I start? i was wondering how to tune the motor and how to fix th pedals or at
Customs services and international tracking provided, Leave feedback about your eBay search experience - opens in new window or tab. Wed May 31 2006 want to sell 1979 batavus complete moped 1978 Batavus starflite IN STOCK. orginal perfict condition and running crome shines all around no rust. drdarkie at yahoodot com please give me information , where I can get 'BELT DRIVE' for my Batavus mat-o-mat 1963. I'm a complete ignoramus when it comes to engines (or anything mechanical) and I'm having a hard time starting it. Pedal to start.Nice bike. Thanks! June 3, 2000 Many thanks! 6 juni, gezocht een in goede staat verkerende batavus bilonet transport ik betaal een goede prijs en je krijgt er drie oude bij om te restaureren, en het verhaal waarom en voor wie is geweldig -- louis My grandfather asked me to find info out on his Batavus he puchaed in 1979. ROCKFORD, ILLINOIS, USA, Wed Oct 03 2007 1978 BATAVUS RARE MOPED WITH ONLY 679 ORIGINAL MILES. Also any Batavus moped. zeer speciaal en zeldzaam in originele staat, Sat Oct 14 2006 jan90396planet.nl looking to verify model year
thank you -- dave.dedrickson at Thank you very much!BrandonDuarte, Sun, 3rd Sept 2017
new jersey, Mon Nov 10 2008 Can you help me out? You appear to be visiting us from Nederland. detailed pictures I would be very grateful. Is it considered a 'slow', -- Anthony R. Tremblay -- artremblay at porkysjunk at yahoodot com 49cc. Lowell, MI, USA, Mon May 17 2010 If you need help just email me. batavus moped Anyway, my question for all of you is this; Does someone own a Batavus Whippet, or does any of you guys have a photo, because I'm the very proud owner of a Whippet. The forks, fenders, frame, handlebars and engine swing arm were refinished black. Maybe someone can give a decent concerning this matter.
Christine Schouwburg -- creations at ameritech.net, August 28, 2000 VERY NICE CLASSIC MOPED!

Spanish Missal 2020,Nom De Chien Japonais Avec Signification,E Coli Under Microscope 400x,Amazon Shopper Gold Status,One World Furniture Net Worth 2020,Arrange The Following Steps Of Protein Synthesis In The Correct Order,Religion In Frankenstein Essay,Billy Garland Death,Interesting Diseases To Write A Report On,Little Britches Audiobook,Saul Consuelos Occupation,Car Lift Rental Bay Area,Upc Lookup Google,La Flamme Streaming,Diego Brando Voice,Famous Blue Heelers,Eva Coupeau Actress,Lucius Smith Lowe Family Tree,Zoo Med Paludarium 36x18x36 For Sale,Skyrim Se Mod 3pco,N'jobu Name Meaning,Tropico 6 Roads,10 Facts About Australian Federation,Confessions Of A Paper Addict Cut Files,Computer Group Membership Refresh Interval,Survivre Film Streaming Vf,Cobra Rev 33 Release Date,Jim Warren Engineer,Dawn Concentrated Dishwashing Liquid,Where Is The Crown Emoji On Iphone Keyboard,Watch Tv In Japanese,Jacobs Ladder Bass Tab,空から降る一億の星 最終回 動画,Dominion Hours Gfw,There Are No Accidents Quote Einstein,

  • 1Carb Mods
  • 2Exhaust Mods
  • 3Clutch Mods/Repair
  • 4Cylinder Port Timing Mods

This is a list of performance modifications you can do to make your Batavus (M48 engine) go faster.

Carb Mods

The ideal float setting for an Encarwi.

Float pin and seat

  • The top of float should be 12mm to 12.5mm (with an un-worn/new tip) or 12.5 to 13mm below pin tip (with a used/worn tip). Hold the float in one hand and twist the pin at the bottom to adjust the float.

The best way I found to tune in Encarwi S25 carbs is to start with the top of the float pin tip at 12.5 mm .

Now plug chop for WOT top speed. Say a 56 works, but you are to rich at low speed 1/2 to idle throttle.

Batavus Moped Repair Manual

NOTE 1 mm of pin tip to float is 1.5 to 2 jet sizes at WOT, adjusting the float is how you adjust/change your 1/2 to idle throttle jetting.

So a 12.0 mm float to tip size 56 jet WOT jetting at 13.0 mm float to tip needs to be 57.5 to 58to have the same WOT jetting and with a 13.5 mm float to tip chang you need a 58.5 to 59 jet.

So you need to lower the float 0.6 mm and up jet one size to have the same mix at WOT with a leaner 1/2 to idle throttle.

You adjust top of Float to tip of pin for low speed and jet size for top speed together and replug chop.

Fast Bat out

Fuel system cleanliness

Check out the condition of the gas tank and look for rust on the inside .You need to disassemble the petcock and spray with carb cleaner. Check the petcock pickup tube and screen filter in the tank and replace the plastic tube with a 1 1/2' long brass tube (1/2' on reserve) so you don't pick up rust . Install a BIG in line fuel filter and new fuel line from the tank to carb. Then mix up some new premix and see how well it flows out at the carb.

If fuel flows okay, pull the carb and disassemble in this order:

  1. TURN FUEL OFF.
  2. Remove the air filter assembly and spring clip.
  3. Push the choke spring up to remove the choke cable.
  4. Remove spanner nut cover and spanner nut holding slide and throttle cable.
  5. Set a drain pan under moped.
  6. Remove flange bolts holding carb reeds.
  7. Pull carb and reeds check the reeds.

If the reeds and gaskets look okay, dissect fuel system in this order:

  1. Remove the bolt holding the fuel line banjo fitting. In side the banjo bolt you will find a very small screen filter with O-ring.
  2. Remove float cover/seat housing (carb top) by unscrewing the two screws. A light tap with a screwdriver handle should free it if it's a little stuck.
  3. Remove gasket and float.
  4. Remove main jet holder.
  5. DON'T USE CARB CLEANER ON THE O-RINGS, FLOAT, BANJO, or SCREEN FILTER. With these parts SET OFF TO THE SIDE, clean all other parts with cemtoole B-12.
  6. Check the float pin and seat. Set the float to the specifications listed above.
  7. drill a 1/16 vent hole in carb above choke lever into top of fuel bowl
  8. Reassemble in reverse.
  9. Reattach assembly on moped and check for air leaks.
  10. Ride and do a plug chop to check jetting.

Exhaust Mods

This mod is for the M48 engine with the 26mm exhaust system.

Materials Needed

  • One 6mm X 1mm pitch die
  • One 1/4 inch drill bit.
  • One die grinder or dremel
  • One mig welder
  • One 6mm X 1mm pitch tee nut
  • One 6mm X 1mm pitch locking nut
  • One 1/4 inch fender wisher
  • One steel tube 1/2 inch ID X 1 inch long .
  • One steel tube 5/16 inch ID X 7/16 inches long
  • One small computer fan guard /cover.
  • One Bing jet #60

Procedure

  1. Remove exhaust system.
  2. Clean de-carbonize the exhaust system. See Cleaning the muffler for suggestions on this procedure.
  3. Watch this video on YouTube.

Aftermarket Exhausts

Motion Left Mopeds (MLM) has a bolt on performace pipe for the M48 Starflight. It has been available at Treatland[1] for some time.


Link to pipe[2].

Clutch Mods/Repair

The way this centrifugal clutch works is that the crankshaft all the way to the right spins and is rotationally connected to the clutch hub (#21). The groove in the clutch hub holds the clutch spring (#18). As the engine hits higher RPMs, the hub will naturally spin with it and the clutch spring will expand as it rotates faster and 'flings' outwards. Since the hub's groove has a ramped radius inside, as the clutch spring grows in diameter it will be forced in an axial direction away from the engine center. This causes contact and friction with the pressure plate (#63), which in turn captures the clutch plate (#14). The clutch plate is tooth-connected to the clutch housing (#71) (all these parts sit within the clutch housing), so that will spin and its V-belt is connected to the pulley (#74) which changes the gearing to your rear wheel. Off you go!

SOOOoo, these clutch mods are attempting to reduce the weight of the spring (by replacing the ball bearings inside with something lighter) so that the clutch will engage later (aka higher in RPMs). This is because the less weight there is in the spring, the more resistance there is to the spring expanding so you fling that spring out only if you're going faster. This way you are closer to the power band and accelerate faster when the clutch actually does engage.

When you start this bike, the clutch cable compresses the starter leaf spring(#7), which temporarily connects all these pieces together, but from the opposite side of the clutch plate (compared to the motor running). So that pedaling will drive the v-belt from the wheel, to the clutch hub, and then (with the clutch plate compressed) to the crankshaft to start the motor. This is just a simpler, reverse version of the bike running.

Preliminary

Batavus clutches can have a .025' to .125' gap. Any gap over .150' means it's time to replace the disk or shim.

  1. Check for missing or flat anti-rattle springs.
  2. Take the 31 7mm bearings in the spring out. Tap the spring with a small hammer where it twists together to help unseat it and untwist it in a large bucket .
  3. Remove/sand all rust from inside the spring/housing.
  4. For this step, I used 1/4'OD stainless steel ball chain because it won’t rust, but any 1/4' ball chain will work or cut plastic tubing into 5/16 inch lengths . The maximum OD is 0.265 inches to 0.245 inches. I found that 0.250 inches OR 0.255 inches works BEST.
  5. Cut plastic tubing into 5/16 inch lengths = 8 inches to 8 3/8 inches total length with 6 OR MORE BALLS into the spring!
Free Moped Repair Manuals, Catalogs, Diagrams and Advertisements

Clutch Mod 1 High RPM With all 1/4” ball chain.

  1. Use 8 inches to 8 3/8 inches total length of 1/4”OD ball chain, with the links pushed together.
  2. When loading the spring use a old razor blade to hold the balls in (sand the cutting edge down).
  3. Twist spring backwards 2 1/2 turns bring spring ends together and twist together foreword.
  4. Lay the spring on a flat block of wood. Tap the spring with small hammer where it twists together to seat it.
  5. The total spacer’s MAX GAP should be 3/8 inches with the spring installed.
  6. Grease spring and Re-install on bike.

Clutch Mod 2 Mid RPM 1/4'ball chain and 6 stock 7mm ball bearings.

  1. Cut 1/4' ball chain into three lengths of 8 or more balls.
  2. Load the spring starting with 1 stock 7mm BALL bearing, then a length of ball chain, then 2 stock 7mm ball bearings, then a length of ball chain, then 2 stock 7mm ball bearings, then a length of ball chain, then 1 stock ball bearing.
  3. When loading the spring use a old razor blade to hold the balls in (sand the cutting edge down).
  4. Twist spring backwards 2 1/2 turns bring spring ends together and twist together foreword.
  5. Lay the spring on a flat block of wood. Tap the spring with small hammer where it twists together to seat it.
  6. The total spacer’s MAX GAP should be 3/8 inches with the spring installed.
  7. Grease spring and Re-install on bike.

Note:

Adjust the ratio of ball chain to 7mm bearings to fine tune engagement of clutch. Just be sure to evenly distribute the weight to reduce vibration and provide even pressure to the plate.

e.g. slightly lower rpm engagement with better grip: 2 BBs, 4 chain links, 4 BBs, 4 chain links, 4 BBs, 4 chain links, 4 BBs, 4 chain links, 2 BBs.

Clutch Mod 3 Just run the spring empty

Batavus Moped Parts

  1. Some just run a empty spring and run it.
  2. Grease it and install on bike.

Notes

  • The balls won't get wedged into where spring twists together.
  • Remove all rust from inside the spring/housing.
  1. Having nothing in the spring can, over time, chatter and/or sing then kink, flatten, twist, and fry your clutch.
  2. The spacers and or balls wont let the spring kink and twist and flatten etc.

Cylinder Port Timing Mods

Batavus M48 cylinder port timing/map mods.

Power band 5,100 to 7,400+ RPMs, peak power at 7,125 RPMs

Port tuning to get a power band between 5,100 and 7,400+ RPMs, with peak power at 7,125 RPMs.

This port timing is for running OVER size piston's, it will kill all low end power with the stock bore.

  • Weaker then stock low end power with 32%+ more top end.
  • Needs lower gearing (12/50 = 4.17:1.... 11/48 = 4.36:1) or a 42mm+ over bored cylinder for strong low end power.
  • Piston speed at peak power m/s 9.12
  • Piston acceleration at peak power m/s2 14069
  • HP approx 4.7
  • Displacement 47.75 cc
  • Bore 40 mm
  • Stroke 38 mm

Exhaust port

  • Exhaust port duration 164 degrees
  • Exhaust port opens 98 degrees after TDC
  • Exhaust port opens 24.3 mm after TDC
  • Port height .................13.7 mm
  • Port width ...................25 mm
  • Polish exhaust port
  • The exhaust port should open .933' after TDC

Intake/transfer ports

Batavus Moped Manual
  • Ports open 120 degrees after TDC
  • Ports open 30.5 mm TDC
  • Intake / transfer ports duration 120 degrees
  • Ports height:................. 7.5 mm
  • Ports width:.................. 17 mm
  • Make the transfer ports point away from exhaust port
  • Transfer ports need to open at 1.205inches after TDC.

Power band 4,500 to 7,000+ RPMs, peak power at 6,750 RPMs

Cylinder port tuning to get a power band from 4,500 to 7,000+ RPM's, with peak power at 6,750 RPM's.

General info

  • Strong better than stock low end power with 25%+ higher top end. Can run it all day at WOT.
  • HP approx 4.0+
  • Displacement 47.75 cc.
  • Bore 40 mm / 1.575 inches.
  • Stroke 38 mm / 1.496 inches.
  • Stock 26mm EX with power band modification

Carb info

  • S-25 Encarwi Carb, modded to inlet 15mm high X width 13mm, venture 12.2mm, out 12.4mm .
  • Set carb float 12.5mm pin tip to top of float
  • Carb jet S-25 #58 to #62.
  • Or mod a Dellorto SHA 14/12 Boar opening at air filter to 16mm and taper down to 13.5mm stop 3mm's from brass tube Jet #54 to #58.

Intake info

  • Stock intake modifications: 12.4 mm in 12.2 mm out. Top sped 37 MPH
  • Hand made intake for S-25 Encarwi Carb with mods to Carb, 13 mm in out mach reed block. Top sped 39.MPH
  • Hand made intake for SHA 14 /12 with mods to Carb, 14.2 mm in out mach reed block 39.MPH.

Reed info

  • Stock reed block. deburr
  • Or replace stock reeds with super thin carbon reeds by drilling out rivets to remove old reeds and taping to install new reeds, and removing the center bridge to make it a big 2 pedal.
  • 4-40 tap and 4-40 x 1/4 or 3/16' phillips pan head works perfectly. (4-40 x 1/4' stick out a little on the inside)
  • Polini yellow reed paper .25mm thick
  • make a 1/8 ' shim to go in be-twine the reed block and Engine case, so the reeds can open further.


Timing/spark plug

  • 0.065' = 19deg's BTDC to 0.075' 21 degrees BTDC Max.
  • Stator plate at mid point +.
  • Spark plug NGK B8HS, or BU8H set plug gap .017' to .021”.
  • New points gap: .0155” to .016'.

Cylinder modifications

  • Cut top of cylinder .024”. to .044'. stopping at the top cooling fin (Note: Dome of piston should rise 1mm or .039 inches above cylinder at TDC This should give 16.6mm or 0.655 inches (NO LESS) between the top of the piston dome and the fin side/top of the cylinder head where the spark plug gasket sits on top of head at hole. (You can use a tire tired depth test to gauge it if you cut into the sides to fit. This is good for for timing too.)
  • Mill head. To set gap, mill ??mm off head -- the tip of the spark plug must be 1mm (0.039 inches) (or more) away from the top of the piston dome at TDC. You're looking for an approximate compression ratio of 9.4:1 to 9.6:1 Max. If you go higher than that, it can overheat the engine or piston, cause pinging, or make you use less spark timing (which will result in less power at 6,000+RPM’s).
  • Use one base gasket. Torque the head to 8 ft lbs (not 11 ft lbs like the manual says). Don’t break it! When torquing down the head, do it in four steps: First to 2 ft lbs, then 4 ft lbs, then 6 ft lbs, then 8 ft lbs. Also make sure to torque the bolts in a criss-cross or 'X' pattern (for example, bottom left, top right, bottom right, top left) for each step.

Exhaust port

  • Exhaust port duration 152 degrees → port height is 12.5mm ovule-shaped (like Stew’s head or a football), width 24.5mm.
  • Exhaust port opens 104 degrees, 25.5mm, or 1.005 inches after TDC. (not top of cylinder)
  • Port height 12.5 mm (0.492 inches)
  • Port width 24.5 mm (0.964 inches), = to 60% of bore.
  • Polish and (taper exhaust port opening on piston side) don’t brake a ring.
  • The exhaust port should open after the piston moves 1.005”=25.5mm down from TDC (not top of cylinder) or 104.Deg's ATDC.

PLEASE CLICK ON IMAGES TO SEE LARGER VERSION

  • Exhaust port with ruler 13mm, X 24.5mm.

  • Exhaust port height is 13mm, width 24.5mm.

  • EX port open at 102.5 degrees ATDC

Intake and transfer port info

  • Ports open 121.5 degrees, 31mm, or 1.220 inches degrees after TDC. (not top of cylinder)
  • Intake / transfer ports duration 117 degrees
  • Ports height is 7 mm (.275 inches), the shape of the transfer ports is like a long long tear drop pointing away from the exhaust port.
  • Transfer ports openings must not taper or point on the exhaust port side of the transfer port opening.
  • Ports width is 17 mm (0.669 inches). Make the transfer ports point 25 degrees away from exhaust port.
  • Taper and deburr the transfer ports. Save the last .5mm (0.020 inches) of porting for hand touch-up and polishing.
Moped

PLEASE CLICK ON IMAGES TO SEE LARGER VERSION

  • Exhaust port height is 13mm, width 24.5mm.

  • Exhaust port left Transfer Port right

  • Exhaust port height is 13mm, width 24.5mm.

  • Transfer Port left Exhaust port right

  • Intake / transfer Ports open 121.5 deg ATDC.

  • Piston at BDC =180 degrees ports open

  • transfer Port

Power band:

  • Power band starts at 22MPH=3,800 RPM's.
  • Kicks in at 24 MPH=4,350RPM's, peaks at 37+ MPH=6,750 RPM's.
  • Fades at 38 MPH
  • Four strokes at 7,000 RPM’s = 39+ MPH with the stock carb and reeds.

I still have strong better than stock low end power with one cylinder base gasket with a duration 152 degree or less. Over 154/156 degrees and you start losing low-end power BIG time.

PLEASE CLICK ON IMAGES TO SEE LARGER VERSION

  • MR bill gives ok

  • Degree wheel

  • Other side of degree wheel

  • Port flowing info

  • Port flowing info page 2

Related Information

A whole series of videos on Batavus Repair. Current repair videos include:
The Batavus is Bad Video
The Tools of the Trade
The Great Batavus Clutch Mod
Encarwi Carb Tutorial
Informational page on both Batavus Laura M48 and M56 engines. Lots of stock information and modification instructions/suggestions. Other links on this page don't work, so to be safe download anything you need before it disappears.