Sunlite easy off freewheel 24 tooth cost $8-20 dollars (note all costs are approx..) Source: http://www.amazon.com/Sunlite-Easy-Off-Single-Freewheel/dp/B00ZDT9E6O/ref=pd_sim_468_4?ie=UTF8&dpID=519w6F0a-4L&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=15HD4NY23E5M29RJNX5V
Sunlite trike free wheel adapter cost $13 Source: http://www.amazon.com/Sunlite-Trike-Freewheel-Adapter-Screws/dp/B000AO7H84
Low profile wheel bearing from McMaster Carr cost $10 each Source: http://www.mcmaster.com/#standard-mounted-bearings/=11h8my1
D axel ½ inch diameter, 1 foot length, from McMaster Carr, cost $10 Source: http://www.mcmaster.com/#rotary-shafts/=11h8ob7
Zinc 4 or 4.5 inch V pulleys from McMaster Carr, cost $12 Source: http://www.mcmaster.com/#rotary-shafts/=11h8ob7
V belts: from McMaster Carr: length depends on particular geometry of your motor, axel wheel setup Source: http://www.mcmaster.com/#v-belts/=11h98zy
Cost approx.: $8-15 dollars, depends on length.
V belt tensioner: use a small, 1.5 inch Zinc pulley cost $5 http://www.mcmaster.com/#die-cast-zinc-pulleys/=11h9f3m
1/8 inch polypropropylene sheet 24 by 48 inches from United States Plastics corp: cost $14
(material to cut circular disc wheel flanges) Source: http://www.usplastic.com/catalog/item.aspx?sku=42603&gclid=CjwKEAiA04S3BRCYteOr6b-roSUSJABE1-6BL2g1EnZsAtWOZAb-UUF4Vkg2EAgz1WGE97rTfrKgyhoCf6rw_wcB
6 inch lawn mower replacement wheels, cost approx. $6 each Source: http://www.mcmaster.com/#lawn-mower-wheels/=11h8tkw
Roller skate replacement wheels and bearings for passive cars, approx. cost $40 for 8 wheels Source: http://www.amazon.com/Choice-Inline-Wheels-Clear-Blue/dp/B004UODTTQ/ref=sr_1_12?s=sporting-goods&ie=UTF8&qid=1457621571&sr=1-12&keywords=roller+skate+wheels
Electric motor for new engine and crank car (uses #40 bike chain), cost $65
24 Volt 350 Watt MY1016Z3 Gear Reduction Electric Motor with 9 Tooth 1/8" Bicycle Chain Sprocket Source: http://www.monsterscooterparts.com/24v-350watt-gear-reduction-motor-9tooth-bicycle-chain-sprocket.html
The Electric motor that I used for the old, original engine is discontinued. Make sure you look
At the physical dimensions to make sure it will fit in the tighter constraints of the old engine design.
There are many options for 24-36 V, 35-50 watt, no. 25 chain scooter motors available from monster scooters, at website below http://www.monsterscooterparts.com/trsc/rec-categories/motors1
motor speed constrollers: approx. cost $30-50 but depends on the motor watts and voltage you choose. Monster scooter sells motor kits with controllers at the link below: http://www.monsterscooterparts.com/trsc/rec-categories/motor
Chain sprockets and chain sizing and link sections and tools:
Please note that the 80 toothed, #25 mm sprocket used in the old, original engine is also discontinued. You can find Sprockets at : http://www.monsterscooterparts.com/trsc/rec-categories/sprockets1 #25 Chain at : http://www.monsterscooterparts.com/trsc/rec-categories/chains
#40 bike chain: from local bike store or anywhere on the net, including amazon.com
Chain link tool to adjust size of bike chain: Topeak 2011 Update Universal Chain Tool: cost $14 http://www.amazon.com/Topeak-2011-Update-Universal-Chain/dp/B005EP95ZC/ref=sr_1_1?ie=UTF8&qid=1457622651&sr=8-1&keywords=bike+chain+cutter
chain link: KMC MISSING LINK II Bicycle Chain Link (7 and 8-Speed, 6-Pairs) cost $7 source: http://www.amazon.com/KMC-MISSING-Bicycle-8-Speed-6-Pairs/dp/B00K7YIVGE/ref=pd_sim_468_4?ie=UTF8&dpID=410qcocQBFL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=156W5RYQWC22Q6VCZWWH
chain tensioners (cost $7-10): http://www.monsterscooterparts.com/trsc/rec-categories/chain-tensioners
Hardware: because the train car frame and trucks are made of wood, most attachments including wheels, mounted wheel bearings, etc. are usually connected using appropriate diameter and length lag bolts with appropriate spacing and lock washers. Wheel, flange, V pulley assemblies use appropriate length no 6 screw bolts, lock and spacing washers, and nuts.