Boxerworks.com

Hi, on removal of the right side piston this morning we found the head
had incurred moisture damage, ( possibly from the bike sitting idle for several weeks
at a time through our Summer, which is a very humid period ),( COULD THIS BE POSSIBLE?? )

So I've gone and ordered a 1000cc Power Kit from Motoren Israel ( $1,008)
Has anyone here dealt with these guys before? I'm wondering how long it
will take to arrive and what their service reputation is like.
They appear to be the only business selling a power kit compatible
with R75/5s with no Mods needed. What sort of increase in Horsepower/Performance
etc. can I expect? Cheers Jeff.

Everything I have ever had shipped from Germany by DHL has taken around five weeks, which suggests to me that part of the way is surface shipping.

My last parcel was stuck in customs in Hamburg for 12 weeks which sort of confirms my suspicions.

Unless they use seaplanes.

I would check with MI for a tracking number, - if they give you a DHL number then get a cup of tea and a nice book and settle down for a wait.

Results from a hop up vary with the skill of the person who does the work - just before he sold it to me the PO of my 800 cc G/S had OEM 1000 cc barrels and pistons fitted , and the heads overhauled and twin plugged, by the Canberra BMW back yard Guru .
Cost him $3000- incl a couple of old Jap coils and the stock ignition, and he ended up with a vibratory slug.
He was told that the vibrations were caused by the different weight pistons and couldn't be fixed without rebalancing the crank, and he decided to cut his losses and sell out.
A Boyer Micropower ignition and matching coils, the air box and exhaust opened out, the timing set by test up my usual test hill and everything else spot on boosted the speed at the top of the hill from 95 kM/hr to almost 130, and it is now the smoothest of my bikes too.

So be prepared for a little time effort and expense to get the full benefit from the change.

I got the kit for my 1975 R90 last winter. It came within 3 weeks. Very pleased. This is the same kit that is produced by Siebenrock. The pistons and pins were within 2 grams of each other. I balanced the rods to make up the difference. Make sure you get the one for 75 and older so it will fit in your 97mm block holes.

Yep, got a tracking number and I emailed Sylvia at M.Israel to confirm whether it was sent by Air or Sea.
He says he sent it by DHL Premium Air Freight so heres hoping it arrives sooner than later!
Sounds good Matt, yeh I definately ordered the Pre 1975 kit. Will I have to mod the Exhaust system at all ?

boxertwinjeff wrote:Yep, got a tracking number and I emailed Sylvia at M.Israel to confirm whether it was sent by Air or Sea.
He says he sent it by DHL Premium Air Freight so heres hoping it arrives sooner than later!
Sounds good Matt, yeh I definately ordered the Pre 1975 kit. Will I have to mod the Exhaust system at all ?

Stock pipes are just fine, since you are staying with stock heads. Your stock carb jetting will probably be OK. You might want to upgrade to R90 heads (42mm intake 40mm exhaust) at some point. Then you would jet it like a an R90 or R100 with the small 32mm Bings. Even then, the stock pipes are what you want. No since going to R100 big valve heads since your pistons will be designed to work with the small chamber of the /6 and /5.

I'm sure you'll be happy with the kit. Not only have you added cc's, but you've vastly improved cooling and durability with the Nikasil cylinders.
If you didn't have MI do it, you will need to put the PR tube in. Ask about that when you have to do it. It's not difficult, but you need to get it right.

" MI," do you mean Micropower Ignition yes?, Why do I need to upgrade to this? Can you recommend a
suitable MI for my R75... I don't get the PR Tube comment you made?.. I imagine my Mechanic might be aware
of these points you mention, as hes an experienced Aircraft Engineer, and has been working on Bms
for ever. Jeff.

boxertwinjeff wrote:" MI," do you mean Micropower Ignition yes?, Why do I need to upgrade to this? Can you recommend a
suitable MI for my R75... I don't get the PR Tube comment you made?.. I imagine my Mechanic might be aware
of these points you mention, as hes an experienced Aircraft Engineer, and has been working on Bms
for ever. Jeff.

No.

He meant Motoren Israel (MI). If you didn't have them put the pushrod tube (PR) in, then ask questions before you do it yourself.

And I think those cylinders use the later biger push rod tubes.

Garnet wrote:And I think those cylinders use the later biger push rod tubes.

Yes. But they fit fine with the old /5 block and head with the right (post 76) seals.