First build shopping list.. what have I forgotten?

Just trying to total up build costs before I get in too deep lol. I've made a shopping list for my first build, not sure it's complete. Would love your thoughts on what else I might need to add! :)
I'm starting with a pretty reasonable roadgoing mountainbike. I'd like to keep as much of it's functionality as a bicycle as possible, as I'll be hitting that kill switch often (It'll be illegal to ride on public roads).
Here's a quick pic of my bike loaded up for a trip to the beach (I've added more cargo space now with front lowrider panniers), this is 70 miles from home.. took me 28 hours to get home against a headwind, including needing a couple of meals and a sleep halfway lol. List follows under pic :) :)

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Okay so here's the parts I THINK I need to get motoring:

Transformercycles : 69.7cc 2-stroke slant-head motor kit with 8mm studs and NT Speed carb (£200)

Torque wrench (3/8") 10-80NM range (£24)
aftermarket fuel filter (about £5.00)
aftermarket fuel tap (under £10)
Copper Kote for head gasket (£?)
JB Weld or equivalent U.K. product (£?)
Shrink tube 6mm diameter
High temperature silicon hose LONG like on Fabian's bike (£? U.K. supplier?)

U.S.A stuff:
SBP : Head Stud kit M8-1.0 ($10)
SBP : Engine Hardware kit ($10)
SBP : 2 Stroke HD Shifter kit ($200)
SBP : engine sound dampeners ($14)
SBP : Front engine mount large ($15)
SBP : Silicon tube 6" ($7)
SBP : NGK Iridium BPR7HIX or NGK BPR6HIX ($7)
SBP : Carb O-ring and Exhaust gasket ($5)
SBP : Head Gasket 8mm ($5)
Kingsmotorbikes.com : 2.5L Rear gas tank ($25) MAYBE
Kingsmotorbikes.com : centre kickstand ($25)
JNMotors : Jaguar CDI ($75)
JNMotors : HP Walbro Carb Kit +RSE Reed Valve Kit (Stage 1 or 2????) ($190) to fit when I ...
get it professionally ported for best power in mid range revs. (£??)

Make and bolt on some extra cooling fins to the cylinder head and insert silicone sound dampening blocks between all lower fins.
Make a larger chain guard for the jackshaft kit, and one for the left hand side for enhanced trouser safety lol. :p
Correct the transfer ports according to instructions on dragonfly75.com, using JB weld or equivalent U.K. product.
Make a rain/splash protector for the air filter.


Wing mirror (£10)
Motorcycle helmet (£50-£60)
Wide tyre liners (£?)
FSA Pig Headset (£10)
Probably fit my spare Marzocchi suspension fork too.
Schwalbe Big Apple LiteSkin Kevlar Guard Folding Tyre (£50 pair)


(£365 + a few items not yet priced-up. for local parts)
($588 + shipping. for the U.S.A. parts)
($588 = £355)
(£365 + £363 = £728 + shipping from U.S.A.)


Petroleum-based oil, and castor oil to break in. (£?)
High quality synthetic oil to run.

Nice new rear wheel (<£100) optional.
Schwalbe Ice Spiker Wired Tyre (£70 pair)

I'll try to get all the locally available stuff first so I can check sizes etc before ordering U.S.A. stuff.
It's a bloody expensive hobby this isn't it? hahaha

Anything else you think I need? Anything on here I don't need or is mismatched to the other parts?
 
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@ FurryOnTheInside

plus you need to get the Rock Solid Engines (reed valve compatible) Walbro style (diaphragm) carburettor kit, 'with thermal isolation spacer'.
 
Thanks for the response Fabian!
I thought diaphragm carbs were just for changing altitude/ air temperature, without having to rejet? :confused:
I was thinking, perhaps in my ignorance, I was going to carry spare jets and maybe a spark plug. Having only read a little bit on the forum about it, I thought reed valves were only to stop backspray after the motor has been ported. I'm really ignorant about motors though lol, I'm hoping I can learn as I play, and that I won't discover things I need or "need" that aren't available in UK for minimoto bikes, pit bikes or go-karts and have to stop playing for months while I wait for parts. I would imagine diaphragm carbs aren't used in those vehicles though as they don't tour.
I don't reallyy want to buy anything from Austrailia since I've managed to find pretty much everything in U.K. and U.S.A., and I'm hoping to get the U.S.A. stuff sent over in one big package as a gift (duty free) from one of my internet ladee friends lol. Is there a U.K. or U.S.A. supplier of these? Anyone? :eek:
So just how essential is the Rock Solid Engines (reed valve compatible) Walbro style (diaphragm) carburettor kit, 'with thermal isolation spacer'? What does it do that a NT Speed carb and pocketfull of jets wont? I will be going up to nearly 1000 meters on rare occasions, but I'll stay at sea level nearly all the time.
 
Forget the idea that one type of carburettor will make more power than another type; given the same venturi diameter. The laws of physics dictate that only a specific amount of air can move through a specific sized hole for a given negative pressure drop over atmospheric, irrespective of manufacturer brand name or design.

If the optimal air/fuel ratio is achieved, any carburettor (regardless of design but with an identical venturi diameter) will make approximately the same power.

The big advantage of a diaphragm carburettor is the user friendly method of adjusting air/fuel ratio through external screw jets, making it a simple affair to get the jetting absolutely perfect in a timely manner as opposed to spending hours disassembling and reassembling a float style carburettor; (spilling fuel everywhere) endlessly mucking about with fuel jets till the jetting is optimised, or sometimes not optimised.
Another notable point is that diaphragm carburettors do not seem to leak fuel; keeping things relatively clean.

Reed valve intakes by design tend to significantly reduce "backspray" as you call it (otherwise known as reversion) on any two stroke engine; ported or not. They also help to smooth out power delivery through the rev range.
Through their mechanical action they keep more air/fuel mixture in the crankcase thereby improving crankcase compression which helps to better atomise fuel droplets when forced through the transfer ports at high velocity.
Everyone has a preference for a particular concept and it's merits but a side benefit of a reed valve intake is reduction of intake noise, which i find the most attractive part of the design; more so than the improved low and midrange torque afforded by the reed valve intake.

JN Motors (located in the USA) sells Rock Solid Engines products and the associated accessory parts like the Walbro style (diaphragm) carburettor adapter for the reed valve intake. Unfortunately JN Motors does not sell the thermal isolation spacer which is "essential" to providing a thermal barrier between cylinder and diaphragm carburettor; allowing stable carburation.

If you require more information do a Google search for: "Walbro Style Carburettor for Rock Solid Engines Reed Valve Intake"
 
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Damn. I was hoping the "Speed" carb would be a little bit better. the kit I'm thinking of getting is a bit more expensive than most and I thought this was one of the reasons to pay more. :rolleyes:
Okay so the diaphragm type carb is few seconds with a screwdriver job, whereas an NT or NT Speed carb is a messy disassembly not suited to roadside adjustment when a sunny day turns to snow blizzard. Makes sense to go with the diaphragm carb then. :) I guess they're okay with high fuel tanks as that's what you have on your bike. All threads I've found so far on diaphragm carbs are related to 4-strokes or problems with non-gravity feed, or some such topic, never mentioning this ease of adjustment.

It did seem counterintuitive that any motor would have an open "hole" there and not a one-way valve of some sort. Good to know it is useful even before I get the porting done as that'll take me a while to do(I intend to ride this thing as soon as I've built it and I won't want to stop!). Anything that reduces noise is a good idea to me. I loveee cycling in the open air and listening to 'la Mer' by my side as I ride so I want to hear her whispering to me, and not just hear the motor sucking! :rolleyes:
Aha, thanks for that, didn't look through JNMotors site for anything apart from the Jaguar CDI so hadn't realised this stuff is available from them. :) They have a daunting number of options though, stage 1, 2 or 3 I have no idea what that means or how tro choose haha.. much more reading left to do on this I think!! :)
I'll have to ask my nephew's go-kart race team mechanic if he knows about thermal isolation spacer/material when the time comes.

p.s. ouch! they are expensive! :eek:

p.p.s. I just bought a new road-ish bicycle. Got a great deal. I'm really happy! Now I won't mind losing use of the 26"er while I play *cough* I mean work on motorising it. :)
 
the kit I'm thinking of getting is a bit more expensive than most

If you want to get the job done properly; having excellent usability as well as dependable reliability, it "will" become a costly affair. There is no point trying to brainwash yourself into thinking otherwise because the wallet does not lie, unless you are using someone else's credit card to fund the experience.

Anything that reduces noise is a good idea to me.

From personal experience the reed valve intake does not make for whisper quiet intake noise; far from it, though it does reduce intake noise from "unbearable" to "irritating", which is a heck of a lot better than "unbearable".
Reducing exhaust noise is a simple matter of affixing 2 & 1/2 feet of (1/2 inch internal diameter) high temperature, chemical resistant silicone hose to the exhaust tip, as silicone hose seems to absorb noise terrifically well without significantly detracting from engine performance.

I'll have to ask my nephew's go-kart race team mechanic if he knows about thermal isolation spacer/material when the time comes.

Because diaphragm carburettors are compact in size, they have a very small internal fuel volume which is susceptible to heat soak from the cylinder; made even worse when the engine is down on it's knees; working it's guts out with virtually next to non existent air flow over the engine or carburettor. Under those conditions, the cylinder becomes a furnace; channeling high levels of heat into the carburettor which will easily vaporise fuel in the small passages, should there be no method employed to block this thermal path.

Okay so the diaphragm type carb is few seconds with a screwdriver job, whereas an NT or NT Speed carb is a messy disassembly not suited to roadside adjustment.

I have tried 3 different types of float style carburettors (standard NT, Delorto SHA clone and genuine Delorto SHA) and after much messing about achieving optimal air/fuel ratio on each variant, i went back to the standard NT which proved to be equally reliable and carbureted equally well, though annoyingly messy when making jetting changes, in comparison to the cleanliness and user friendly adjustability of a diaphragm carburettor.
 
Whoa thanks for detailed replies Fabian! And thank you so much for all your replies and threads on here and elsewhere, I've really learned a lot tonight. :bowdown: :) :) Always find your posts are usually the most relevant to the type of riding and build I'm aiming to do anyway. :)
the kit I'm thinking of getting is a bit more expensive than most-- I meant the original "complete" motor kit, the basic china motor kit lol.. now after finding out how to get the best out of a china kit, it seems a lot of the extras and "better" parts that come with that kit are going to go unused anyway haha!
All the box-pusher china kit dealers assure me that theirs is the best china kit and internally it's better made, better materials blahblahblah sales blurb. I'll ultimately not be using most of the parts that come with the more expensive china kit; so is that slant head (and 8mm studs, and someone painted the motor black), that the more expensive motor comes with, enough to think I have a better chance (yes I realise it's impossible to be sure) of good things inside?

Absolutely it all adds up. I'll be using lots of tips I've found on here to reduce the noise and vibration and hope that every little will make my build feel and sound noticably better. I saw your exhaust whatsit, and fully explained tutorial on fitting it, and I will definitely be copying that as one of my sound moderating mods.. when I find a place where I can get the hose. :)

Makes sense to fit a thermal isolation spacer then. :) JNM walbro + reed kits inexplicably come without one if the product pics are to be believed; so I'll have to email them in a bit and ask if they're going to give me one with the kit or not.. if no luck there then I have the email for RSE (just can't use their shop because apparantly the UK is blacklisted haha I love that, makes me feel like an outlaw! :devilish: ) Otherwise, I'll have to look into making a rough homemade one.. no idea what sort of plastic they're made of so idk how hard that is yet. :unsure:

Adjusting a float style carb is obviously a job to be done at the workshop, not out on the side of the road while getting covered in snow/rain/hail lol. My idea that I could carry a few spare jets and an oily rag was clearly optimism through ignorance and I'm glad I found out and thankful you told me! I've just been looking at the tutorial you did on fitting your carb and reed valve and it looks as easy to adjust that diaphragm carb out on the road as adjust a deraileur. :)
I now have a choice of three carb kits on JNM, a stage 1 stage 2 or stage 3 (none of them pictured with a thermal isolation spacer).. I have no idea what they mean by stage 1, 2 or 3.. maybe it's like a Mk1 Mk2 Mk3 thing, I really can't tell so I'll ask them about that when I email them about this "missing" spacer. It is shown assembled on a motor so it seems it does not include longer bolts to accomodate a t.i.spacer either, or an M4 bolt with a hole drilled through lol. I'm getting the SBP hardware kit, so obviously those bolts will be too short too haha I will end up travelling to the city to find bolts and trying to drill a straight hole down one.. every bike I build is like this!! They NEVER make it easy do they? :giggle:
 
They NEVER make it easy do they? :giggle:


When dealing with this hobby/transport, the first thing you come to realise is that the very second your preferred options deviate from what's shown on a vendors website, life become a nightmare of impossible difficulty, no matter how much common sense you try and bring forward to the discussion.

The same difficulty applied to the Sick Bike Parts shift kit, which is supplied without chain tensioners and only now (2 years down the track) has an optional set of chain tensioners become available. Prior to this new option i had to spend time messing around designing my own chain tensioners which proved to solve all of the (massively annoying) chain tension issues during the early days of operating my bike with the shift kit, even though the shift kit in itself was a fantastic product.
There were times when i was on my knees begging Sick Bike Parts to design chain tensioners for their shift kit, but my words fell on deaf ears. Fortunately the chain tensioners designed by Sick Bike Parts are far superior to my own designs, hence i have installed them on my bike.

In the same context, i have spent over a year trying, or better said, begging Rock Solid Engines to design and manufacture a thermal isolation spacer for the reed valve diaphragm adapter kit, because issues showing up in the real world of long haul every day operation were not showing up on the engine dyno with relatively short run times.

I can say the same of the Jaguar CDI which is a terrific product for improving power and extending the life of 2-stroke Chinese bicycle engines, but it annoyingly lacks an easily adjustable external user interface.
 
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The different "Mk" specifications listed on the JN Motors website relate to different levels of component parts and also different diaphragm carburettor sizes. You will have to decide which level of componentry suits your needs and desired outcomes.

A thermal isolation spacer needs to be made out of a high temperature engineering plastic; to resist deformation at high temperatures (to prevent air leaks), because it is under compressive stress.
From conversation with Tony at Rock Solid Engines he made mention that the plastic used in his thermal isolation spacer is made from a high temperature aerospace engineering specification with thermally stable properties - plastic definitely isn't plastic.
 
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it looks as easy to adjust that diaphragm carb out on the road as adjust a deraileur. :)

Yes, it is that easy - makes you wonder why people persist with float style carburettors when there is clearly a much better option for a 2-stroke engine, considering 2-stroke engines are very susceptible to changes in atmospheric conditions; requiring jetting changes to maintain optimal carburation; sometimes on a daily basis.



Adjusting a float style carb is obviously a job to be done at the workshop, not out on the side of the road while getting covered in snow/rain/hail lol. My idea that I could carry a few spare jets and an oily rag was clearly optimism through ignorance

You have placed your words well; being massively over optimistic, some might call it delusional and some might more appropriately call it masochism :devilish:
 
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