Wheeler 2,468 Posted January 2 (edited) Well after yesterdays ride & lots of previous thoughts, I’ve decided to build my never before opened up spare 300 motor & build a 400BBK to replace my 355BBK in the atv currently. Here’s my plans.. JR Trikes 400BBK (ORDERED!) JR Trikes Valves/Springs/Seals (ORDERED!) Webcam 40C & Rockers (ORDERED!) 250BR Chain & Cam Gear (ORDERED!) EBC DR6 Clutch Kit (ORDERED!) HL Outlaw Springs (ORDERED!) Replace Centrifugal Clutch & One Way Bearing (ORDERED) Front Axles (ORDERED!) Seals/Bearings (ORDERED) (IF there is ANY play in the crank, it’s getting one rebuilt at Mr Crankshaft!) **NO PLAY** I don’t want to have to open this engine back up for years to come! Ill be using Motts Machining for the Jug & Head work My 355 already had the rest of supporting mods like the 300ex carb & exhaust, Ricks CDI, K&N filter, 424, Disc Brakes ect… I do have to get myself another oil cooler & a fan to keep things running cool! Edited March 29 by Wheeler 5 1 Share this post Link to post Share on other sites
_Wilson_™ 6,427 Posted January 2 Did you not sell the 355 ? Or do i have my wires crossed ? Anyways ... Tuned in for the build! 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 2 19 minutes ago, _Wilson_™ said: Did you not sell the 355 ? Or do i have my wires crossed ? Anyways ... Tuned in for the build! No @_Wilson_™ I still have the 355 in the quad. Runs strong.. u didn’t miss anything there… 1 Share this post Link to post Share on other sites
_Wilson_™ 6,427 Posted January 2 Thanks for some reason i thought you had purchased another bike.... Maybe I'm thinking of the engine (future) 400bbk 1 Share this post Link to post Share on other sites
Fishfiles 19,670 Posted January 3 So is the Trike BBK a one time deal ? --- What I mean is , are the sleeve and / or the piston both one time use items , if the piston is damaged there is no oversize , so the sleeve would also have to be replaced when a new piston or rings are needed ? 1 Share this post Link to post Share on other sites
_Wilson_™ 6,427 Posted January 3 Good question fish..... Never accurred to me to ask. Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 3 3 hours ago, Fishfiles said: So is the Trike BBK a one time deal ? --- What I mean is , are the sleeve and / or the piston both one time use items , if the piston is damaged there is no oversize , so the sleeve would also have to be replaced when a new piston or rings are needed ? yes fish, I “believe” this is it… at 400cc there isn’t room for error… 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 3 20 hours ago, _Wilson_™ said: Thanks for some reason i thought you had purchased another bike.... Maybe I'm thinking of the engine (future) 400bbk i did purchase my old 300 back from my buddy who I sold it too after I swapped plastics. But only kept the motor, front diff, front driveshaft ect. 1 Share this post Link to post Share on other sites
_Wilson_™ 6,427 Posted January 3 (edited) Oh crap! Yeah NOW i recall it...... Cause you debated on building a complete machine from that one, right ? Edited January 3 by _Wilson_™ 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 3 1 minute ago, _Wilson_™ said: Oh crap! Yeah NOW i know recall it...... Cause you debated on building a complete machine from that one, right ? Yes sir! That’s correct. I don’t have much more to buy, & she will be ready for the teardown! 1 Share this post Link to post Share on other sites
_Wilson_™ 6,427 Posted January 3 I'm not EVEN going to ask what the top speed of this new will be..... Lol! ...your not going nitrous yet are you? 1 1 Share this post Link to post Share on other sites
jeepwm69 7,206 Posted January 3 Need lots of pics when you do the build! Might want to look at using a 450 Foreman cent clutch while you're at it. I think it requires grinding the inside of the clutch cover a bit, but otherwise bolts on. 2 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 13 Clutch, springs, cam chain, 250BR cam gear & foot pegs all here! 4 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 19 More parts arrived today. Front Axles & they weren’t cheap. Unreal how some parts are really expensive for these old girls now!! 2 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 21 (edited) More progress today. This engine has never been apart! So clean & good shape. I have to send the rockers for hard surface & cam as core for the 40C to Webcams. I’ll have to get the front left corner tapped out as it’s the only one that snapped off. It’s like that on my 355BBK as well. Edited January 21 by Wheeler 3 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 21 Unreal how much thicker the 250BR cam gear is... I wonder why they changed it out for the 300??.... 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 21 Decided to keep going.. 3 Share this post Link to post Share on other sites
Fishfiles 19,670 Posted January 22 11 hours ago, Wheeler said: Unreal how much thicker the 250BR cam gear is... I wonder why they changed it out for the 300??.... I would guess saving money was the reason ---- I wish they would have made the timing gear on the crankshaft replaceable --- I have seen on 1st gen 300s the parts micro finche shows a replaceable gear , but have never seen or heard of a replaceable gear to exist ---- I would guess when that crankshaft gear gets out of pitch it really shortens the life of the chain and the only way to fix it is to replace the crankshaft 1 Share this post Link to post Share on other sites
jeepwm69 7,206 Posted January 22 6 hours ago, Fishfiles said: I would guess saving money was the reason ---- I wish they would have made the timing gear on the crankshaft replaceable --- I have seen on 1st gen 300s the parts micro finche shows a replaceable gear , but have never seen or heard of a replaceable gear to exist ---- I would guess when that crankshaft gear gets out of pitch it really shortens the life of the chain and the only way to fix it is to replace the crankshaft If that were the case then I would think that first GEN cranks would bring a premium, assuming Vince could replace that gear and that a replacement gear is available 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 22 Ya only was to fix the teeth is the crank. I agree a replaceable gear would be the way to go! 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 24 Cam core & rockers sent off for hard welding! 4 Share this post Link to post Share on other sites
Snow Camo 237 Posted January 27 On 1/23/2023 at 7:04 PM, Wheeler said: Cam core & rockers sent off for hard welding! Web? 1 Share this post Link to post Share on other sites
Wheeler 2,468 Posted January 27 54 minutes ago, Snow Camo said: Web? yes sir. 40C 1 Share this post Link to post Share on other sites
Snow Camo 237 Posted January 27 (edited) Rock on man! Any cam grind in mind? Disregard. Realized 40c is the grind. Lol Edited January 27 by Snow Camo Share this post Link to post Share on other sites
Fishfiles 19,670 Posted January 27 On 1/22/2023 at 9:23 AM, jeepwm69 said: If that were the case then I would think that first GEN cranks would bring a premium, assuming Vince could replace that gear and that a replacement gear is available Whether or not they even made some cranks with a removable gear I don't know , I do know , when I first got into 300s and needed a crank , the parts prints showed the crank with the gear being removable and a part number for that gear , but now the prints have been revised and the gear is no longer shown Share this post Link to post Share on other sites
