newbie from the uk

Welcome to KDXRider.net! Please take a moment to introduce yourself, and meet the group.
Post Reply
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

newbie from the uk

Post by ogre52 »

hi all just joined i'm from lancashire in the uk .i have just bought a kdx420 originally from the US that needs restoring.i'm more of a roadie than an off roadie got a z1 currently restoring,z1a thats done,gpz1100b2 done,katana 1000 needs doing,cbx1000 in boxes,cb750k0 done,rd350lc needs doing ,bmw g650 gs (pants really).back in the day 35 yrs ago ha had a rm125(totally unreliable) ,dt175(cracking bike) rings went on it still got me home. so has u have gathered i'm a bit of a novice again.so really looking forward to learning from you guys and probably going to need a lot of help.i'm an engineer so not frightened about restoring it really but i know parts are pretty hard to find.1st question is what is the afternmarket silencer on it cos the cap has no holes in it apart from the screwed rod in the middle and it blows out around the outside kind of where the fins are.had to see if it runs it fired up with a remote fuel bottle pretty quickly but died pretty quickly throttle cable all over the place.then it was a bugger to start .eventually it did kept revs up a bit smoked me out .blowing at front of exhaust at the header and there was black residue like oil comin from there and out of muffler is that crank seals.heres some pics when i bought it.going to need lights etc that will be fun.if you spot anything wrong be grateful for the heads up.
cheers guys
my kdx1.jpg
my kdx1.jpg (450.39 KiB) Viewed 4766 times
my kdx4.jpg
my kdx4.jpg (465.8 KiB) Viewed 4766 times
my kdx5.jpg
my kdx5.jpg (326.29 KiB) Viewed 4766 times
mykdx3.jpg
mykdx3.jpg (278.24 KiB) Viewed 4766 times
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: newbie from the uk

Post by KDXGarage »

Welcome to kdxrider.net. Thanks for signing up and getting involved.

Here's a link with the parts diagrams. You can click on the part number to see which other models came with that exact same part.

That is not the stock spark arrestor. As an example of the handiness of the diagrams in the link:

Image
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

Re: newbie from the uk

Post by ogre52 »

Yep thanks cmnsl do the schematics as well i think they are in holland wot are ur thoughts on the black residue is it because it took ages to get it started again poss flooded or more like crank seals did feel oily.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: newbie from the uk

Post by KDXGarage »

A lot of neglected bikes show that. Some with just incorrect jetting do it also. I think it is a bit early to jump to checking the difficult to check things before the easy to check things. How's the air filter, plug, reeds?
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: newbie from the uk

Post by bufftester »

So the silencer on that bike is a Supertrap, they were big in the 80s. You could adjust your back pressure by changing the number of baffle plates on the end (it was a gimmicky marketing campaign). The black oily residue coming out is the remnants of old pre mix, or "spooge" as it is affectionately known in the 2T world.
Looks as though all the big parts are there, including plastics and tank, so that will help. First order of business should be to tear down and clean the carb, noting the needle and jet sizes/positions. New filter, check reeds and all gaskets. New springs and gaskets for the exhaust. The Supertrapp can be cleaned by removing the end plate and all baffles. Compression and leak down checks should be high on the list as well. Looks to be a fun project. Any idea how it ended up in the UK?
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

Re: newbie from the uk

Post by ogre52 »

Yep dkmotorcycles over here imported it they swept and still sweeping through california i think brought thousands of bikes since the classic scene exploded a few yrs ago. Might be a stupid question how do you do a compression test on this keep booting it over cos obviously on my bikes i turn it over on the battery but they turn over a few times to read true compression and please enlighten me on leak down test on 2t. Already got some good info thanks guys
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: newbie from the uk

Post by bufftester »

Compression test pull the plug, insert gauge and cycle the kickstarter by hand a half dozen times. Leak down will check your overall crank seal health, involves pulling the pipe and carb and plugging those holes, place the piston at BDC and pump up to 6 psi (don't go over 8 or you can induce a seal failure). Leak rate should not exceed 1 psi per minute.
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

Re: newbie from the uk

Post by ogre52 »

Thanks for that great info on leak down test
User avatar
doakley
Gold Member
Gold Member
Posts: 1241
Joined: 02:58 pm Mar 10 2016
Country:

Re: newbie from the uk

Post by doakley »

I've always done the compression test with WO throttle and rapid full kicks until pressure doesn't climb any further, engine cold. I was taught no matter what, always use the same procedure so you can compare to past readings. Each his own I'm sure.
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

Re: newbie from the uk

Post by ogre52 »

thanks for that waiting for a workshop manual at mo but goin to do all these checks before i strip it
kdxsully
Supporting Member
Posts: 739
Joined: 08:28 am Apr 21 2019
Country: United States
Location: North Cackalack

Re: newbie from the uk

Post by kdxsully »

bufftester wrote: 05:30 pm Jan 11 2020 Compression test pull the plug, insert gauge and cycle the kickstarter by hand a half dozen times. Leak down will check your overall crank seal health, involves pulling the pipe and carb and plugging those holes, place the piston at BDC and pump up to 6 psi (don't go over 8 or you can induce a seal failure). Leak rate should not exceed 1 psi per minute.
What do you guys like to use to plug the exhaust and intake? I’m curious. Plumbing parts from Lowe’s maybe?
I like turtles
User avatar
bufftester
Platinum Member
Platinum Member
Posts: 3455
Joined: 06:03 pm Oct 31 2012
Country: USA
Location: University Place, WA

Re: newbie from the uk

Post by bufftester »

I have two big rubber plugs (like they use on test tubes, etc) that I found at a swap meet of all places. One of them I drilled a hole and tapped a shcrader valve in for pumping with a bike hand pump, it gets held in the carb boot by the clamp, for the exhaust I shove it in and hold it in with some safety wire run between the 2 spring mount holes. You're only going up to 6 PSI so it doesn't take a lot to hold it in place
ogre52
Member
Posts: 8
Joined: 11:56 am Jan 08 2020
Country: uk

Re: newbie from the uk

Post by ogre52 »

sounds like a great idea and a cheaper option
User avatar
Goat
Supporting Member III
Supporting Member III
Posts: 720
Joined: 03:22 pm Oct 22 2019
Country: USA
Location: Clinton, WA

Re: newbie from the uk

Post by Goat »

Y’all got me inspired to finally check the compression (+ I had the tank off). Like I shoulda done before I plunked down my cash.

Happy day. Bacardi & KDX get the same fire power rating.

No wonder I can’t kill this thing with my lack of fine tuning skills. Some nice PO musta been in there not too long ago.
Goat
95 KDX200
22 KX250
Post Reply